manual on hatchery production of seabass and gilthead seabream pdf

‘Pumping station Seawater walls ‘Pumping stations to hatchery connection and wastewater treatment Boiler room Electiety generator room 2.2__ SEAWATER SUPPLY, DISTRIBUTION AND DRAINAGE

Manual on Hatchery Production ot

Seabass and Gilthead Seabream Volume 2

by

Alessandro Moretti

Maricoltura di Rosignano Solvay Srl

Via Pietro Gigli, Loc Lillatro

57013 Rosignano Solvay

Livorno, Italy

Mario Pedini Fernandez-Criado

FAO/Morld Bank Cooperative Programme

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PREPARATION OF THIS DOCUMENT

“This is the second and final volume of a manual on hatchery production of seabass and -gữhoad soabream, It part othe programme of publication o he Inland Water Resources and Aquaculture Service (IRI) The manual has been written based onthe direct experience 9l lechoieans and managers of commercial hatcheries operating inthe Mediterranean, Ii intended to assist both technicians entering tis field as well as investors intrested in

‘evaluating the complexity of hatchery production of seabass and githead seabream

“The manual has been prepared by the authors under the overall support and supervision of FIRI and direct technical coordination of Maria Pedi, Aquaculture and Fisheries Development Officer ofthe FAWorld Bank Cooperative Programme Numerous coleagues have colaborated, contrbuting comments to sections of the manual, and ideas and assistance fori inalization, The contibufen to this volume of Bigde Loix, STM Aquatrade

‘i, Lamar Sil Udine, Licnio Corbi, Maribrin Sl, Massimo Caggiano, Panitica Pugliese

‘Spa, are really appreciated The assistance inthe editorial work an final presentation ana

‘graphics given by Jose Luis Casta, Alessandro Lovateli, André Cache, Patrizia Ravegnani {and Emanuela d Antoni has also been invaluable

Moret, A; Pegni Femande2-Criado, M; Vella, R

‘Manual on hatchery production of seabass ana githead seabveam Volume 2

Rome, FAO, 2008 152p,

ABSTRACT SSeabass and githead seabream are the two marine fish species which have characterized the

‘evelopment of marine aquaculure in the Mediterranean basin over the last three decades The

‘substantial increase in production levels ofthese two species, nal of very high value, has been possible thanks to the progressive improvement ofthe technologies involved inthe production of fry in hatcheries As a rest ofthis technological progress, mare than one hundred hatcheries hhave been bul nthe Mediterranean basin, working on these and other similar species At present the farmed production ofthese two species driv from halchory produced ty i far greater than the supply coming from capture fisheries

‘The dovelopment of these techniques, based cxginally on Japanese hatchery techniques, nas followed is own evolution and has resulted in what could be called a Mediterranean hatchery technology that Is stil evowving to provide higher qualty animals and to reduce the costs of production This is a dynamic sector but has reached a level of maturity which mers the production ofa manual fr hatchery personnel that could be o intrest in other parts ofthe wold

‘The preparation ofthe manual has taken several years, and due to recent developments has led

to substantial revisions of sections The manual Is not inlonded to be a tnal wor in hatchery design and oporation but rather a publication to document how the Industry works Tho authors hhave preferred to include proven procedures and designs rather than to orient this publication to research hatcheries that are not yet the standard ofthe sector

‘The manual has been divided in two volumes, The fist one was finalized in 2000, and covered historical background, bology and lite history ofthe two species, especialy hatchery production procedures This second volume Is duged in four pats Inthe fist, I tes to cover the aspects Felated ta hatchery design and construction, from sia selection to halchery layout, and deserption

Of the various sections of a commercial hatchery The second part covers engineering aspects Felated to the calculation and design of seawater makes, pumping stations, ydraule creuls, and pumping systems The tid part deals wih equipment in the hatcheries such as tanks, titers, War sterizer, water aeration and oxygenation, lomperalure contol, and auxtiary equipment

‘The last part covers fancial aspects This section, ratner than explaining the way lo calculate cash flows, testo highight aspecs that managers and investors should consider when entering this business, Volume two also includes a series of technical annexes, anda glossary of scien fang technical terms used inthe two volumes,

CONTENTS,

‘1.1_CALCULATING THE SIZE OF A HATCHERY 1 1.2_SITE SELECTION CRITERIA 2 113_ENVIRONMENTAL FACTORS ‘Sea conditions 2 3

Meteorological factors a

‘Site related factors a 1.4_SOCIO-ECONOMIC ASPECTS 4 1.5_EXISTING FACILITIES, 5 1.6_HATCHERY LAYOUT 6 17 BRQODSTOCK UNIT Calculating the size ofthe stocking facilities 8 8

Quidoor [aciiles Indoor facies 10 3 Spawning tanks mat cueui

‘Space requirement calculations

11_ROTIFER Production Iaeiiias CULTURE AND ENRICHMENT

Support systems Equipment

Space requirement calculation

1:12_BRINE SHRIMP PRODUCTION Production laeiiias AND ENRICHMENT

‘Support systems Equipment

‘Space requirement caleulation SBöEBEE

1.48 LARVAL REARING UNIT roduction facitias

Support systems

Space requirements

1.14 WEANING UNIT Production facilities

‘Support systems

‘Space requirement calculations

1.15_SUPPORT UNITS ‘Pumping station

Seawater walls ‘Pumping stations to hatchery connection and wastewater treatment

Boiler room Electiety generator room

2.2 SEAWATER SUPPLY, DISTRIBUTION AND DRAINAGE SYSTEMS 3

2 ‘Sandy coastline with a low gradient WATER INTAKE 34

‘Seawater intake on a rocky coast

‘Seawater intake placed inside a natural or arificlal enclosure

24 DESIGNING WATERINTAKES ‘Geometry and structure of seawater intakes on a sandy coast — se 29

Calculation and design of structures against sea storms ‘at

‘Geometry and structure of seawater intakes on a rocky coast Hydraulic section of seawater intakes a2 4

2 IDERATIONS ON THE CHOICE OF WATER INTAKE 4

26 MAIN PUMPING STATION, “Dry" pumping station tt “

"Wer" pumping station 46 2.7 DESIGN OF THE PUMPING STATIONS Design of the main pumping station a7 48 Design ofthe secondary pumping staion 4ã

2.8_CONSIDERATIONS ‘Type of pump set FOR THE CHOICE OF THE PUMPING STATION — 48 l& low estimation

2.10_PIPELINES Feeding the main pumping station AND CANALS

Connecting the main and secondary pumping stations

Distriouting water in the hatchery

Draining water from the hatchery

2.11_DESIGN OF PIPELINES, OUTLETS AND CANALS Design ofa pipeline working under pressure

Ovediow outlets Canals and gutters

2:12_ DESIGN OF HATCHERY HYDRAULIC CIRCUITS: EXAMPLES OF CALCULATIONS

‘Water inlet system Desorption

Water outlet eystem Description

Calculation

Main gutter as a triangular ditch in the ground (Bazin formula)

‘Main guitar as-a rectangular channel in concrete (Bazin formula)

‘Main gutter a5 a round concrete pipe (Manning- Strickler formula

2.14 BUMBS ‘Types of electrical pumps

‘Turbine pumps information requirements for the design of a pumping system

2.14_DESIGNING Calculation of the pumping systern THE PUMPING SYSTEM

Power absorbed

2.45_CONSINERATIONS Choice of pump category FOR THE CHOICE OF A PUMPING SYSTEM

Choice ofpump ype Choice of numberof pump sets

‘Which type of UV lamps to choose Selection of UV sterlisers

OXYGENATORS AND AERATORS

Increasing disolved oxygen content of water

Improving oxygen transfer ito water

Ar and oxygen diffusers, Injection of oxygen into a pipeline Injection of pure oxygen using a submersible pump

Pressurized mixers

Estimating oxygen requirements in tanks

‘OXYGEN MONITORING AND REGULATING SYSTEM

Control systems

‘Measuring dissolved oxygen

‘Oxygen supply management

WATER TEMPERATURE CONDITIONING

AUXILIARY EQUIPMENT FOR FRY MANAGEMENT

4.1 INVESTING IN AHATCHERY Project design

‘Structure and construction typologies

Timing and production

Economies of scale and modular design

Depreciation

Pints to consider for financing of a hatchery

Investments and maintenance

95 96

97

99 99

Enz HATCHERY DESIGN AND

Gross mistakes in dosign andor construction can sk full production season even botor itis stato

In addon, temporary solutions always cary the risk of far from optimal rearing conditions, leading to sisease outbreaks in sh arvae

This second pat ofthe manual deals with he principles and guidelines forthe design and construction ofa commercial hatchery for gthead seabream and seabass

‘This chaptor describes how to calculate the size ofthe hatchery and how to select the appropriate se algo deal wth the design of production facies Tha function and the selection of hatchery systems and technical equipment are also described, focusing onthe most widely adopted technical solutions in Mediterranean hatcheries Special attention is ven tothe deseripion of the seawater intake, and to water dstnbuton, reciculaion and treatment systoms, as they are among the most sensitive

‘components ofthe hatcery

1-1_ CALCULATING THE SIZE OF A HATCHERY

In order to design a marine ish hatchery the investor has to have a clear idea about ts production target A decison onthe sizeof he hatchery i a fundamental prerequisite before starting the search for suitable i69, or before stating the tecrnical design or the financal plan,

In partcular, the foloving issues shouldbe addrossed:

+ main fish species seabass,githead seabream or both),

* secondary species (other fish, clams, shrimps),

+ yearly targets as number and sizeof fy of each species considered,

* origin of eggs (intemal production or from other sources)

‘whether photoperiod and thermoperiod manipulation to shit reproductive cycles is planned,

* marketing aspects (ish size and season forsale)

‘Any aspect not propery considered during the planning phase may result in tic working conditions later on, requing costly interventions lo correct them (al all possible) and causing production interuptions

1.2 SITE SELECTION CRITERIA

The Mediterranean region Is not uniform Environmental conditions along its coasting vary considerably Habits, customs and technical development of the counties bordering it also show large

‘tfleronces, The analysis of these local factors isthe inal stop in the process of proper design of @ hatchery Infact, the above mentioned aspects play a crucial rol in relation tothe techoical feasibly, but also in keeping the running costs within manageable mis

I may soem absurd, but the vast majority of Mediterranean hatchery silos were not decided on the basis ofa thorough selection process, bu were often already set atthe beginning ofthe project This Absence or scarcity of options Is common both in private and pubic projects In the fist case, the investor usually owns the ste, whereas in te public hatcheries local and politcal reasons may influence the selection ofa particular location ragardess of technical considerations

In any case, when looking fora new site or when coleting information an a preselected locaton the reconnaissance process should consider several well-delined aspects which fall under two broad

‘categories: the natural ervronment and the socio-economic environment,

1.3 ENVIRONMENTAL FACTORS

‘Ais ofthe main environmental parameters of data collected by national services (meteorology, oceanography, sol, etc) provide more reliable to be considered is given below As a ru, historical series Information tan local interviews or spot measurements, which, however ae a useful Too! 10 make a fist evaluation of the sto,

= Low Pollution » Good hatchery conditions SITE

+ Low rocky coast

~ Easy acce:

+ Tap water + Electricity

~ Telephone

‘Sea conditions

+ Seawater temperature is one of the most important parameters because itinfuences ical design ‘componenis such asa seawater intake system (open or semi-closed cru) andthe heating system,

Iemay also have an influence on operating costs and as a consequence, an the overall economic

feasblty of the project In the Nother Meciteranean, due to the fact that both seabass and

giticad seabream brood during the witer and eary spring period, the rather low winter seawater peratures mean that waler heating is necessary fo reduce larval rearing time,

+ Waves (amplitude, length, crection, seasonal and storm condtions) coastal currents (magnitude, rection and seasonal varatons) and tdes (ranges, Seasonal and siorm variations, oscilations)

ate key factors tobe considered when designing the sea water intake They also have importance

fon seawater qualty when polltion sources exist even i they are locate far away Whenever

Possible itis important to collect historical data ser on these parameters rom publ authortios

fr other relevant sources, Local sources should be considered only when no ater information 1

Availabe, orto confirm coleted dala,

+ Seawater qualiy, despite the Mediteransan Stes tobe aveiced ae those atlecied @ common misconception, is usualy sutabe for hatchery cperatons in mest by severe incustal and domes pluton

‘Such areas are found close to lage industal instalation, towns, harbours oF In ver des oF

estuaries Web-water, hough interesting asi tends io have a more uniom temperature troughout the

{yea and far lower nvesiment costs for extraction snot ee rom potental danger Mt shoud prove & Constant and relable ow and be free from polulans such as ammenia,suphur compounds, heavy metals and pestoides To a cenain extent specic treatment can improve is quay, But where

‘dangerous heavy metas are present, their elimination is very cu

Meteorological factors,

+ Winds Prevaing direction and speed The occurence of stang winds or seasonal storms has a ‘70a nftuence on hatchery design Apart from buiding characteietcs planned for windy areas, the

main problem isthe protection ofthe sea water intake, in particular, located in an open area,

His design and size ate directly nkee tothe occurrence of bg waves and strong currents caused

by storms The seawater qualty is also severely affected by strong water movements that re

suspend sediments According lo the type of sea floor, the amaunt of suspended solde may

increase oramatcally under bad weather conditions A ste located in a bay shetered from the

‘dominant winds has important advantages, such as the absence of sttong waves and currents

Under these cieumstances, te constuction ‘treatment of seawater (sedimentation and mecharicalitraion) On the other hand, protected bays: may sutfer trom low water exchange, which means waste water must be discharged far enough of he water intake fs considerably simpiied, a8 is the

‘tom te water intake to avoid any sel-contamination The codking effect of wind a elatvely shallow

‘is is Something that should not be underestimated,

+ Maximum storm intensity ‘and the fist tobe affected by an exceptional storm, Due ots usually considerable cost, the design and frequency The seawater intake is the most agile part ofthe hatchery

intake Tacties should take info account cea conditions under the strongest storm recorded in @

period of 50 yoars atthe location that is being evaluate

+ Ar temperature In many Mecteranean sies, air temperature is an important factor Low ait {temperatures in winter do affect operating costs of the hatchery, and efficient thermal insulation val

'e requied 1 Keep internal ai temperature around 18 10 20°C The use of heated air Blowers for

the hatchery aso provides the necossary venation, Air extractors shouldbe combined with such

lowers to reduce humiity loves inside the hatchery

+ Solar onoray, Togathor with alr temperature, it contibutes to the thermal balance of the hatchery ‘system If considered at desig stage t may alow relevant savings in terms of westment and runing

oats In the aso of hatcheries totaly or partly bul na greenhouse, shades and vention shoud

be provided in late sping, summer and early autumn, according othe location, to prevent overheating

‘Site related factors

+ Coast morphology afects hatchery design and construction mainy in thee ways: n providing a sufcent at area forthe bulđngs, n relation tothe design ofthe seawater intake systom and for

‘seawater qualty Low sandy coasts provde plenty of space, but the water intake yp€aly requres

‘expensive protection (oeakwater, long inlet channels, sedimentation tanks) to prevent cogging and to minimise sand and detrtus uptake A rocky coast usualy has better water quality (absence

of suspended solids quicker retum to normaly after designs are possible, but is hard soil complicates the constuction of structures requiing a storm) ad simpler and cheaper water intake

‘excavation The height ofthe coast above ea level should also be considered, since higher sites wil mean, for a given ‘low, larger pumping stations and higher operational coss In both cases, locations exposed o high waves and sion currents should Needed to protect the wator intake, be avoided du the expensive works + Site accessbiliy Places isolated from the road network wil require approach roads, which represent an adcitonal cost that has o be caretully evaluated

* Avalabiy of facies such as electric, telephone and potable water networks A connection 10 {he high voltage electricity network is a prerequisite, whereas a lnk to potable water networks could bee replaced by alternative solutons Nowadays, a permanent telephone connecion can be replaced by the use of cellar phones, although operating costs would be higher

+ Sources of polluion from human activites (large settements, industial activites, intensive agtcuture, other fish farms in partcuar The selection of the hatchery locaton should tke info Account the presence of important urban setlements,industial harbours and large factories, which fare sources of pollutants and could compromise water qualty condos When ‘niensive

‘gyleulture or Industries are present in the coastal watershed they wil produce pollutants that wil be discharged by rivers in tho coastal areas + ver discharges Even inthe absence of pollution from human actives, river discharges cary sediments from surface runof, that may contibute to excessive siting, This can rapily clog the

‘Seawater intake, or worsen the quay of seawater atthe pump intake + Availabilty to be lowered or rearing water has tobe cooled of eshwator (not potable) Freshwators needed in a hatchery, espocal if saity has + History ‘Abandoned industial areas or former warehouses and dumping sites shouldbe carotuly checked of site: pr uses and experiences Previous uses of the sites may have an impact {or contaminants in bath soi and on the beach before deciding ona st

1.4 INTEGRATION OF SOCIAL, ECONOMIC, LEGAL AND TECHNICAL ASPECTS Site selection is

0 greatly infuenced by socal, economic and legal aspects

'At present a -tech approach inthe design of a marine fish hatchery can assure a viable economic

‘poration, keeping production costs to a minimum and optimising contro! procedures forthe whole production process However, a hitech approach is not always possible in specific locations, both in terms of the necessary technical support, avalabilly of assistance, services, equipment and

‘consumables, and also in terms of socio-economic charactorsties such as avalable manpower, po[teal

‘acceptance, and local traditions and habit

Technical service and repair Even simple equipment such as pumps, ar blowers, Ights, titers and steriizers needs servicing The local avalabilty of qualified personnel ablo to provide spociaisod

‘maintenance and ta intrvene quickly in case of breakdown of equipment should be evaluated Proper

‘maintenance also requires the avallblty of essential spare pats: shops or agents representing the producers of the main equipment should also be easily accessible and thei relabity should be carelully checked If avaliable, and of simlar characterises, localy-produced equipment is best because itis cheaper and easier to sorvice

Building materiats The materials used to buld the hatchery depend stict on the focal level of Industal davelopment and local constuction standards, The choice between prefabricated or ick Duldings should be made only after comparing local construction costs and maintenance costs Manpower Marine fish hatcheries require skied labour The local avalabilty of qualified manpower shouldbe evaluated This s leo linkod tothe relative importance that aquaculture has inthe county

‘That may be reflected in high school or post-graduate spocalisation, fish industrial production, oF

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TH facilities

! Legal aspects Economics

Co nong nang innninindanaai

‘aquaculture research programmes Previous experience wih fish rearing should be essential

‘requirements fore staf such experience does not exist inthe country, the me and cost necessary

to train farm personnel wil have tobe taken into account

‘Stat and management faites When the halchory is tobe sited far away trom inhabited areas,

‘adequate accommodation shouldbe provided forthe staf, For sites that are far rom important cites, provision of extemal technical assistance, as woll as the supply of consumables (sh feed, chemical products and equipment spare parts) wil become more difcut A welhequipped workshop and

‘adequate storrooms should then be included inthe hatchery design

“Legal aspects and permis Al kinds of constraints forthe use ofthe area, either existing orfotaseoablo, have tobe investigated Miltary, archaeological and historical areas usually mean hatcheries cannot be built but other land uses, such as widife protection and natural packs, may coexist with the fish hatchery In addon, the hatchery should comply wih all loca logislation and regulations concerning Constructions, such as maximum heightength, total volume allowed, imitations on the use of some

‘materials and so fort,

‘Tne existence the hatchery isto be built has to be compatible with fish farming The existonce of mtatons 10 a of local development plans shouldbe verified The planned use ofthe coastal area where Possible future expansion of the haichery, such as propery boundaries under diferent ounershi, Should also be checked

Economics The greatest attention shouldbe given to the financial analysis ofthe project overly itis {economically sound Economic factors aso influence the general aspects ofthe hatchery design high 0st of and willbe an incentive to design more compact structures in order to save space high labour oat wl lea! o maximum automation of werking processes to reduce manpower Ahigh market value of the produce wll prviege high investments ana the development of more technologically advanced Producton plans In soveral Mediterranean countres, grants of loans with lower iforest rates than Standard loans are avalablo for new enterprises, making more cost-effective production models possi

1.5_ EXISTING FACILITIES

‘The possibilty of making use of existing facies to set up @ hatchery, is offen an advantage Sometimes, especialy when existing industrial buldings have to be reconvertad, the permission for land use s already awarded and mos of the needed services (e.g energy, reshwater, telephone lines)

are aroady available This is usually attractive forthe investor and itis offen the main reason to decide

to build @ hatchery on an existing facility Buta more accurate evaluation ofthe advantages ofered by the pre-existing facites should always be carried out, with particular emphasis on the possible presence of polutants inthe bulling, sol and facing sea area, 2s described above The advantages Offered by the use of pre-existing faites shouldbe caretlly considered Adaptation ofthe production process fo the existing site should never compromise the basic technical eiteria applied to hatchary esign

HATCHERY LAYOUT

‘The hatchery layout (Fig 8) Is presented following its production units, Criferia to be adopted rather ste for architectural and engineering solutions are:

+ overall economic feasibly ofthe project wih cos fective solutions,

+ raonal exploitation of available space and energy,

+ rational choice of materials and equipment,

+ maximum technical reliably, achiaved through a correct choice of is maintenance, of equipment and the organizalon

* relabity of production methods, obtained through adoption of standard working methodologies based an proven production techniques, ecient use of resources at disposal and ergonomics,

* easy servicing and maintenance,

* adopt flexible solutions o enabie future technical upgrading

ensure optimal hygienic conditions

‘Tho desctption of hatchery production systoms is dvd into two main components:

‘tne production units, where true production actives take plac:

‘the service units, hich provide the necessary suppent to prodiction units,

BROODSTOCK UNIT

“The function ofthis unit i the proper maintenance of adequate stocks of

arent fish to assure a timely supply

‘of fertized eggs ofthe best quay 0

the larval rearing sector

Broodstock units have facilities

placed both outdoors and indoors

‘Outdoors facities are mainiy used

for ong orm stocking purposes, but

‘also fer quarantine treatments and to recover spent or newly captured

‘readers Indoor facts are mainly used fr:

Different tank designs are used for alferent purposes Before going into their description, it lEDecessary to know how to calculate te size of the faciities on the basis of the planned producton

Calculating the size ofthe stocking feciliies

‘The broodstock unt requires enough space to ko9p broeders in healthy condtions so that they

‘ean spawn viable eggs and can be used for

‘mare than one breeding 803500,

‘The total water volume V required for long term

‘rearing of broadsiock can be calculated by

taking into account he folowing points:

+ th total female body weight fbw, which in turn depends on the quantity of eggs needed (his figure can be calculated using the aready described average fomale fecundly, that is Flg 6 - Conofee ank and PVC outot cf seabass and 350 000 for giihead soabream; 120 000 twordays old larvae per kg bow incase

* the total male body weight mbw, which depends on the sex rao (number of males, normally two er female) and the average individual size ofthe males; + the larval survival ate fr the diferent species ta be reproduced:

+ tne stocking density D (expressed in kgf’):

+ the reproductive pattem (gonochoric or hermaphrodite}

+ the number of spawns per year S, plus eventually safety margin forthe stock of 80%

should be 1 kg perm in arge earthen ponds, and upto Sky per in small plastic or concrete tanks

‘The required water volume for species 1 (V,) expressed in miscalculated as

= [tbw, + mbm): Dax, The required total water volume V is calculated as the sum of V; + Ve + Vso which depends on the umber of reared species and adding the 50% safety facto

‘This formula refers oth final standing stock of breeders, where al he roquied biomass epresonted alts peak, When the volume includes also the out-f-eeason reproduction, must be considered hat

it refers tothe adeional tanks placed indoors or contol of temperature and photoperiod

Example calculation of the outdoor tank volume for a small mutispecfic hatchery with an annual requirement (one natural spawning season) of 4 milion two-day old larvae of both seabass and githead seabeeam,

In seabass, considering the average female fecundly conservatively estimated above, we obtain:

+4 000.000 120 000 = 23 kg of females,

‘which wih an average individual weight of 1.25 kg corresponds to 27 females, With a sex ratio of 2:1 {males per female), the 54 males required win average weight of 0.8 kg per male add about 43 kg

“Thus, the total biomass (tba, + mby;) would be 78 kg (33443) and it represonts tne minimal requitement of seabass spauners for one production season,

For githoad seabream we have

4000 000 : 350 000 = 11 kg of females, which with an average individual weight oft kg corresponds o 11 individuals With the same sex rato,

‘he 22 males required, with average weight of 0.4 kg per male, add about 9 kg, Thus the foal biomass (tow + mow) would be 20 kg (1149) and it epresents the minimal requirement of gitead seabream spavine's for one production season,

To cover possibi accidents siseases and stock renewal, an extra 50% shouldbe considered for safety reasons, Therefore, the foal biomass of seabass would be around 114 kg, to which 30 kg of githead seabream breadars should be added,

\Wnh a long tefm stocking densi of kg per min earthen ponds, 114 m? would be required for seabass broodstock and 20 rm, for lthead eeabream, hence a total volume requirement of 124 m

* The water supply canal should fil the ond by gravity through a screened

‘wooden or coneret-made inlet gate + The dyke slope (ato of horizontal to votical) of beth ponds and canals depends on the type of soi used and the dyke elevation With clay sols,

‘ykes higher than 4 m should have a slope of 2:1, whereas for dykes lower than 4 m it Should be 1:1 The internal

de ofthe dyke that moist athe time should have a gent siope than the utr side, usually ory

Pond water depth should be 1.5 m on average, with a 2 to 5% bottom slope towards the ain 10 low for an easy and complete cainage The pond botiom should be propery levelled to prevent the fermaton of pudelos when drained Betore staring he excavation, the possible presence of a high water table (resh ar sea water during high ie) should be checked, as a complete drainage ofthe pond may not be possible

“The deeper area ofthe pond onthe side of he drinioute, shouldbe tne with concrete or plastic liner to acitate harvesting ane cleaning operations,

‘The extemal drainage canal should be deep enough to allow a completo drainage by graviy

‘A suticint aference in love shoul exist betwoen the bottom ofthe pend and hat ofthe inal water ‘discharging point ofthe farm,

i concrete tanks are peterred, the same criteria concerning depth, water supply and drainage should 'e applied The tank walls shouldbe vertical o save space and materal The bottom slope should not

‘excaed 14%, The constuction a reinorced concrete structures in seawater requires a thicket coment layer around the ste! bars o prevent corosion

\Wmhen surface area is nota constant, the separation between two adjacent tanks or ponds should bo

at least 4m to be used as road and to faclitate fishing and broodstock selection operations Iton a {yke, the read should have 0.6 m wide shoulders on both sides to prevent erosion Canal crossings should be covered by steel grids, of by wooden or concrete slabs Pipelines should be batter placed

in pre-abrcated concrete trenches, covered by a grid or concrete slabs required for periodic inspection

[Agroup of smaller tanks should be considered for quarantine of fish collected fom the wil or bought fortemporary stocking and for prophysactic or curative treatments, These tanks should be much smaller (to 6m) 10 reduce the use of drugs and chemicals during bath trealments Fibreglass is quently the prefered materal due to its cost and manageability The drainage design should allow treatment of the effluent prior tots tinal dsposal to avoid the risk of contamination of he surrounding environment with pathogens and dangerous products

During the hottest months, atleast 10% ofthe pond area shouldbe covered to give the fish some shaded areas and a place to rest If necessary protection agains fist-eating birds should also be given

Indoor tacts

The tanks where fish are temporarily stocked to obtain lertlised eggs are usualy placed ina dedicated sector They should bo localed in the quietest comer of the bulding to reduce disturbance to broodstock An adjacent area should be reserved to clean, disinfect and store the equipment of the ‘spawning unit

‘Windows for this indoor section are not strictly necessary as Spawning requires controled Bght Conditions, but they can be insted to renew the ait and feduce humidity inside the Spawning unit Air extractors could

be used in place of winows,

“The toor ofthis unt should be tiled or painted with epoxy Coatings to faciitate clearing, and tommaintain hygienic condtions In

‘order 10 drain the tanks an adequate drainage system made fof sereened channels under the for is required lt should havo a

‘Slope ofa east 2%

“Thermal insulation of walls and roo is advisable in locations wth cold winters to save on heating costs

‘Atramework of zinccoated steel beams suspended over the tanks should be considered to alow the Installation of the main support systems such as heating, water supply and recireuation, ight and

‘lective systems, at and emergency oxygen suppies

‘When considering a water recirculation system, enough floor space close to the tanks should be planned in the design stages to house is various componenis such as mechanical fits, biological fiers, pumps, steriizers, and heating devices Ifthe drains can be placed under the fer, the gutters {ong othe biological titers should be bulk well above the floor love a prevent dit or toxic chemicals

‘such as dsinfctants used ta wash floors, fm entering the recirculation system

‘manual collection ot eggs and broodstock manipulation

In regions with low winter temperatures, the spawning tanks are filed with heated seawater Kept at temperatures between 1M and 18°C To reduce fuel consumption, a semi-closad recirculation system is often adopted Regardless of shape and size, the spawning tanks should fll the following conditions:

+ easy contol ofthe fish population

+ easy accessibility to the tank bottom fr dally clearing;

+ simple and quick cleaning routine:

+ easy replacement ofthe screened out

+ simple out construction fr accessbilly and service;

+ minimum stess for fish at harvest;

+ optimal swimming behaviour of sh;

+ absence of transport problems incase of proabricated tanks;

+ optimal use of avallable covered area inside the buldg, which calls for square or rectangular, rather than round tanks: + simple design of supper systems (water suppyldainage, air supply, power supply, ght)

.Aoeordng to their shape, number and avaiable space, tanks can be arranged in groups or in rows In

‘any case, staff should have easy access toa least 75% oftheir pester The space between rows oF

‘r0ups shouldbe wide enough (0.8 o 1.5) to permit tho use of toes for working routines

Water eireult

‘Spawnersrequite ocean-qualy seawater a a fay constant temperature n the absence of a reliable

‘natural source of seawater atthe right temperature, seawater has to be heated or cooled When the breeding cyce isto be manipulated, a water recirculation system is introduced to reduce heating and Coaling cost This is also used inthe coldest regions were the waler temperature stays below 10°C for mote than 3 or 4 months Recycing systems equi a biter where the toxic ammonia (he main harmful product of fish metabolism) is biologically oxidised into safer nities and nates,

PVC pipes are used to supply and drain water The water citcuit design shouldbe planned as simply

a possible with the minimum number of comers to avoid pressure lasses and the appearance of dead

‘ulation poins where sediments and bacteria could accumulate is components should be

‘assembled by means of fast joints and bolted flanges to facitate cismanting or cleaning and service

‘operations, According fa the wala supply system, ve By graviy or by pumping, PVC pipes should be INP6 or NP10 respectively o stand aiferent water pressure evel Each tank should be equipped with fan independent inlet placed onthe tank rim: a bal valve shouldbe provided to adjust its lw according

to requiremens Tap water should be easly at hand with a few dalvery points and a washbasin for

‘wight effect when igts are tuned on and of Emergency Iights that do not disturb fish could also be installed Large windows shouldbe avoided to prevent direct suight fling on the tanks

‘eration system

‘Air supply is assured by a few coarse difusers placed onthe tank bottom and shouldbe regulated to keep eggs suspended inthe water mass, Plastic needle valves for aquarium or metal clamps (much

‘more expensive) can be used to regulate ar low

‘Overwintoring actities

In focations with mil winter conditions, breeders can remain in ther long term stocking facts al year round except at spavming Ime Where cimatc candions are particularly severe, some precautions have to be adopted In these eases fish holding facies can be

‘protected by a ight cover (a greenhouse for exami9) + deepened (3 to 4 m),

+ shaltrad from the proving winds by means of windscreens, + supplied with heated water

‘These precautions, sometime expensive and dificult put in practice, do not guarantee a completly sale station In the colder locations In that ease, the whole broodstock must be moved into Indoor facitios where the temperature can be kop at 10 to 12°C At these temperatures fish have a reduced metabolism and therefore low feeding requirements resuling in limited production of organic wastes Compared to outdoor facies, a higher stocking density can be maintained (up to 15 kg/m), thus reducing the space occupied by tanks

Conditioning facilities

Ín many hatcheries indoot faites are also used for condoning breeders to delay oF advance their natural sexual maturation cycle and spawning Season In that caso, the condioningspawring areas become permanent faites that occupy a dedicated part ofthe hatchery because othe long residence period needed For practical purposes, such condoning tanks are usually ofthe same design and

‘material ofthe spawning tanks Branders are usualy Kept ata density of upto 15 kai

‘The area is also subdivided into several zones, isolated from each other, where cli lighttemperature regimes can be adopted This requires independent systems for light and water temperature regulation The heating system is ofen coupled with a cooling system, usualy

pump, to provide out of season winter condtions

1.8 LIVE FOOD UNIT

“This units dedicated tothe production of microalgae, rtfers and brine shrimp naupli (Artemia sp.) in large quantities, tobe used as ive feed fr fish larvae

‘The unit has separate sub-unit for

+ phytoplankton and oiler pure str + phytoplankton and otfer bag cut + rotifer mass culture and enrichment, + Artemia naupli mass production and enrichment,

‘laboratory tests,

1 and small volume cultures,

Each sub-unit is housed in a room of variable size wit ted floor and walls and is provided with air contioning, teated seawater supply, fteshwater suppl, air distribution system, working lights, safe lugs, and a drain system Adaplations to the needs of each sub-unit are specie below

‘Th fst three sub-unis should be comiguous to simplify working routines, since they represent three iferent steps ofthe same production process They should be placed close tothe larval reating unit

to reduce transport distance The laboratory services the entro unit, plus the other hatchery compartments There should be, however, a pathalogy laboratory in a separate room, to prevent possible spread ot diseases

1.9 PURE STRAIN AND UP-SCALE CULTURE ROOM

[Algae and rotfer pure strains, as well a5 up-scale cultures (fom small vessels up to 5-10 lire fasksicarboys), should be kept in an al-condltioned foom under stele candtons to avo possible contamination, Floor and wall inthis raom shouldbe tied for easy washing and disinfecton.A smal rain systom i ll that is require since all cuture vessels are kept sealed or aro drained though the

‘washbasin oul An adjacent rom of mal size, wh the same hygienic precautions s reserved for

‘culture dupication and storage of consumables

“The cultures, wheter in test tudes or glas or plastic vassels, are placed on shelves with igh and are opt at a tomperature range of 14-16°C A CO,-enviched ait supply system connected tothe culture

‘vessels provides an addtional source of carton and ensures the necessary turbulence An ideal Solution fer pure strains i lighted incubator where al test tubes are stocked under optimal condtions

‘Asal culture volumes are steiized and prepared in advance, tis room is the only part ofthe ve food unt without a supply of treated seawater Al glassware, water medium and nuitient solutions are serlized belore use, folowing the procedures explained in Volume 1 ofthis manual The equipment for Sorlizaton varies according othe system chosen (see pat for data), andi typically house inthe laboratory orin an adjacent service room A germicidal amp (UV ligt) shouldbe installed to contol the residual bacterial contamination inthe a Noe that this UV lamp must be switched on anly when no staff are inside the rooms, and theretore, security switches shouldbe installed on the door

Support systems

Light is extremely important in algal cuture The rghtsize fuorescent ubes are conveniently placed to

provide a ght intensity of upto 1 000 lux for pure stains and up to 6 000 lux fo larger vessels They

fare placed horizontally under th glass shelves as wall a onthe sides of he shelves and are protacted

trom water splashes by means of waterproot plugs

‘eration is required to create turbulence and o provide oxygen for both algae and ratfr cultures Each

vessel withthe exception of test tubes, is equipped with one glass tube connected tothe air pipe by @

flexible plastichose The aris distributed trough a central PVC pipe wth branches going to each sh

To aoeolerale algal groafh, carbon dioxide Is addled tothe alr blown into the vessels ata volume rate

of 2 Commercial grade CO, bots are connected to the main pipe through a gauge and flowmeter

To monitor its low, a bubbling flask i installed botor the connection tothe main air pipe As carbon

‘oxide is heavier than air, some U-shaped joints ar installed along this pipe to prevent statifcaion

Due othe heating etect of the Highs insta inthe room, at condoning is usualy necessary to keep

the temperatura within an optimal range, The aie condoning should also work inside the repbeation room due fo the prolonged use of Bunsen burners while preparing glassware fr culture repcation

“Tap wator should bo avaiable and a washbasin fr cleaning routines Only the personnel in charge of

this sub-unit should enter this room and they should dip ther boots ina tray filed wih disinfectant

solution

Equipment

‘The equipment inthis sub-unit is mainly glassware for culture duplication and monitoring of alga

cultures Stelized vessels of diferent capac filed with seawater, should always be avaiable for

cdupleabon and up scaling A cupboard is usetul to store al strlized material before use Consumable

{equipment (chemicals to prepare nultent solutions, glass tubes, et.) should also be stored in his sub-

Unit One plastic basin filed with 10% hydrochloric acd solution is required to disinfect pipates attr

Use Used glassware is washed, filed and steriized inthe laboratory orn another dedicated room

1.10_ INTERMEDIATE ALGAE AND ROTIFER BAG CULTURE ROOM

In this sub-unit, algae and rotifers are cultured in large quantities in polyethylene (PE) bags They are

‘Used directly o feed fish tanks (algae), or as inoculum for cuplcation and for larger volumes (algae and

‘otiers) The bags are housed in a dedicated room adjacent othe sub-unit described above The floor

‘ofthis room should be tie to facitate cleaning procedures and should have a slope of a least 2% towards drains

‘Bags and stands

“Two basic designs ag (capac 50 to 150), and a largor one standing inside a wire mesh oyinder (yp to 400) In both of PE bags of ferent capacities aro utilised: a smaller single or double suspended cases, hot extruded tubular PE of 0.2 to 0.3 mm thickness is employed Ths is aa cheap, dlsposabie

‘material that can be shaped according te production needs The bttom of the bag is sealed either by hot welding, orn the case ofthe U-shaped double bags just by knotting, The largest bags are placed Inside a wie mesh cylinder placed ona fibreglass or wooden base that has a V-shaped central cu This shaped cut allows proper placement ofthe bottom ofthe bag,

‘Suspended bags hang trom stands located father inthe centre ofthe room or along the wals The second solution is prterted when transparent walls are used, to fake advantage fof sunlight Stands are preferably made of Zine coated steal to prevent corrosion For the ‘same reason, wire mesh should be plastic coated,

\Wnenever possible, the design should include large windows or glass wall,

‘Support systems This sub-unit is connected to the heated seawater dstibution system through some taps Bags ae filed using flexible hoses which can be disconnected, emptied and placed in a basin with hypochlorite solution for sinection

Due to the heat produced by the aril lighting system, air conditioning may somtimes be necessary to Koop tomperaturos within optimal ranges (18-22°C) Ai temperature contol is required for the hatcheries working with githead seabream inorder to supply the large amounts of algae required fortis species n action,

‘may be necessary o coo! he ai inthe hottest months in order to maintain the algal growth within its

‘optimal conditions

Fluorascent tubes provide the necessary lumination They should be placed to provide an intensity of

£6 000 ux (ange: 4 000-8 000) over the entre cor vericaly, but in both cases, they must be pratacted from water splashes by means of sealed plastic bag surtace They can be arranged either horizontally

‘ea565 or waterroot plugs Allow at least one 36 W tube per smal bag, ana two for larger anes, To save

‘energy, Betwoen four and ten tubes should be grouped and connected to a single such Gas walls

an save energy during the day A light sensor (photocell) can tun the ights on and of Then large windows should be instaled as this will turn this room info a greenhouse, reaching very high temperatures during spring and summer

.Agraon is requied to assure proper turbulence inthe bags and each bag is equipped with two ir hoses (best to use tubing of 6 mm inner diameter) placed near, but nt onthe botom, to avoid siring

the sediment As the water weight keeps the PE fim well satched, air hoses can be put in place by simply forcing them through a vary small hole inthe desiced place The ar ihfbien system ie bul with a central PVC pipe wih branches going to each bag row

Tap water should be easiy available with a fow

alvary points and a wash-basin should be

provided for clearing routines

Besises ilumination, the electric system should

be designed wih afew waterroo! sockets, which

could be used to connect plastic pumps for

harvesting, tansler and inoculum operations All

materia such as swiches, plugs or sockots used

in the electricity network should be waterproot,

with each socket controled by a safety switch on

the sub-unit conto! pane

Equipment

“The equipment in thie subunit includes plastic

containers to produce algae and rotifers (ouckets, funnels, graduated cylinders, containers with a

‘cap for chemicals and nutions, ete) and the

‘lasswareto monitor the algal and roitercutures (Gpetes, Petr ashes, microscope slides, etc) Bags ao lid by means of flexible hoses connected

to the seawator supply points

‘Whereas all rotfer cultures are fitered belore ther restlization, mature algal cultures are directly transferred by means of seltpiring submersible plastic pumps, whose hoses have to be carefully washed and disinfected ator use

‘Acouple of large, fat tanks (with a capacity of about 1 000) filed with disinfecting solution (500 pom Ihypochloite or 10% hydrochloric aca) fs used to disinfect al tools ater use

‘Space requirement calculations

‘The space occupied by bags can be calculated by assessing the planned dally peak consumption of

‘algae and tofer culures for up-scaling Such caleulations should therefore take into account

+ the peak dally amount of rotifers 1 be used as inoculum for new mass culture tanks

* the peak dally amount of rotifers to be re-used to inoculate new bags:

+ the peak daly amount of algae requirements for rotfer duplication;

+ the peak dally amount o alga requirements fr groen water inthe larval rearing unit

+ the peak dally amount o algae tobe r-utized as inoculum for new bags:

+ the average numberof days requiod o abain a mature culture of phyto or zooplankton,

1-11 ROTIFER CULTURE AND ENRICHMENT

In this sub-unit rotifers are cultured in large quantities in tanks of larger capacity than the bags previously described, and are then enriched betore bong led fo fish lavao This production is catied

‘ut ina specie room, usualy adjacent tothe bag culture sub-unit to faciitate the transfer of cultures from ene room lo the athe Floor and walls should be covered with ties for hygienic reasons As harvesting takes place in the same room, involving large quantities of culture water, an ecient Grainage system is require

Production facilities

————=m—— Optimal rearing tanks are round tanks with a conical bottom seth a

capacity ranging between 1 and

44 Thor inner surface can be white gel-coated to improve cleaning, An adequate drain with

a vale atthe cone tip is needed for harvesting operations

‘As thele management requires, frequent observations (water quality monitoring, feeding, feichment and cleaning) these

a tanks are usualy placed in double rows separated by a wooden of

‘hese cultures are static, the temperature in the tanks is maintained wih elecical heaters made of

‘itaniom or with cole tubing al round the tank Due to the water masses involved, an ar heater is usually not necessary

{As algae are being replaced by artical des, only service lights are required

‘Aeration is roquired to maintain adoquate levels of turbulence in te tanks and each tanks ited with air stones placed at about 15 om fom the bottom fo avoid string the sediment At least 5 air aifusers

‘16 used in @ 2m tank: one a the centre, and the other four placed along the wall Around 23 mh of air low perm? of culture volume is required

“Tap water should be at hand witha few delvary points and a wash basin,

“The electricity system should be designed witha fw waterproo! sockets o connect plastic pumps for harvesting, anster and inoculation operations As inthe offer sub-unit, all te material used inthe

‘lectrity syelom should be waterprool, with each socket controled bya safely svateh on the sub-unit contol pane

Equipment

‘The equipment inthis sub-unit should include an array of plastic containers for routine works (buckets, funnels, graduated cylinders, beakers, otc), as woll as large containers fo keep the chemicals, the lassware for culture monitoring (pinetes, Petri dishes, microscope slides, el) and thermometers for routine checks, Flexible hoses wih fast PVC joints connect the bottom valves tothe fiter used during harvesting, Troleys with a flat platform are uselu to transport the Various containers and other

‘equipment used inthis sub-unt Large plastic iters with 60 pm mesh are used to harvest rotifers

‘Space requirement calculation

‘The space occupied by this sub-unit is determined by the expected maximum dally consumption of

‘eters by the larval ish unt, The calculation should therefore take into account

+ the peak dally amount f rotifers to be fed to fish larvae

+ the peak dally amount of rotifers to be re-used to inoculate now tanks,

+ the individual volume and numberof the roifer mass culture tanks,

+ the average density of enriched rotfer at harvest,

+ the average numberof days to got a mature rotor culture

‘The fist point depends on the total number and age of fish larvae being reared inthe larval uit and the feeding requirements, whose estimation is included in Volume 1, annexes 17 and 18, for both sseabass and githead seabream

‘Tho second point isa function ofthe mass cute system adopted to speed up production, enriched rotifers in their log phase can be successfully utlized as inocula to start now tank cultures

‘The third point sa function ot te average ‘and nal fearing periods and adeng a slot margin ako ito account possible losses and cuture crashes dally consumption, adjusted o cover reduced noods ding hal

‘Tho fourth point depends on the rearing conditions, rotfler batches and management A conservative

‘utput of 600 - 900 milion enriched rotifers perm should be considered

4.12 BRINE SHRIMP PRODUCTION AND ENRICHMENT

‘The production of brine shrimp (Artemia) larval stages (naupli and metanaupti) is cartied out in a separate oom, usually adjacent tothe rotfer sub-unit for practical reasons (same treated seawater

‘supply airconditioning system and staf) The design should not include windows or transparent walls, {as harvest of Artomia nauplil requires conditions of total darkness As inthe other unis, the floor and walls should be bled to help maintain good hygienic conditions As harvesting takes place inthe same

‘oom wih tons of culture water being fitered daly an adequate drainage system is necessary (a central

‘maninoe or screened channel cain)

Production faclities

Difarant tank designe have been adopted for brine shrimp Incubation and envichment However, the basic round tank with coral bottom oes near ideal consis in respect of water circulation, aeration

land harvesting, Tank capacity can be usually lower (1 to 2m!) than that of tanks for mass culture of rovers, to give greater production flexi

“The tank ner surface can be painted in white (ge-coated) to ensure in the frst haute of eyst meubaton) and proper cleaning, The tanks must have a transparent window a beter ight fusion (portant near the cone tpt attract naupil at harvest ime by means of ight source A drain with valve at the

‘cone tp is used for harvesting

Duo to he imited routine work (tha required is mainly DO monitoring and enrichment det supply

‘every 12 hour), these tanks should be pastioned along the walls to leave enough tre space atthe

‘cette ofthe room fr harvesing operations

‘Support systems

“The production of Aramia naupli requires high

{temperatures (27-80°C) for optimal hatching rate and high hatching offiiency Therefore,

‘only heated seawater from the same cuit that

serves the rotler and algal sub-unts is used,

‘The heating system should be able to heat

ater tothe optimal temperature ina very short

time (see below for technical details) To

prevent neat dispersion inthe room and cooling

‘ofthe tanks, an ait heater shouldbe installed to

‘maintain room temperature at a neary constant

level

‘The best output is obtained under strong ight

‘and aeration conditions A lamp should

‘therfore be installed in each tank, I should be

‘made with 1 of 2 fluorescent tubes delvering

2.000 lux at he water surlace A sealed plastic

container or waterproof! plugs are

‘ecommendes since the strong ait bubbling in

the flanks produces a vaporized salt water

spray

To provide the sương aeration needed, an

‘open-ended PVC pipe (ho) i placed in each

tank near the belem, & ball valve allows

regulation of the aie low, which should be about

168 mh per m? of incubation volume a

‘Tap water shouldbe at hand wit afew delvery points and wash-basin for cleaning implements The elðeIiely system should be designed with a waterpro! plug near each tank 10 install ether a Submersible electric heater or the harvesting ight As usual, the electricity system shouldbe waterproct, with each socket contoled by a safety switch on the sub-unit contol panel,

Equipment

\When large amount of cysts have to be handle, It may be practical © add a separate area equipped with several smaller round-conical tanks (50 to 100) for cyst disinfection or decapsulaton This area ier rom the main Artemia room in that an eficient system for alr ronewalextraction Is neode This is because toxic reagens that produce gases are used inthe process of decapsuiaton

The equipment inthis sub-unit should also include plastic containers diferent sizes fr routine work (buckets, funnels, graduated cylinders, beakers, etc) as wel as large containers forthe chemicals Used in the dsiniectonidecapsulaton process, the glassware used for culture monitoring (pipettes,

2 x

Petr ashes, microscope slides, eto.) and thermometer Fexble hoses with fast PVG janis are used

te connect the bottom valves to the tite ulized for harvesting, Toles wih a fat platform are useful

to transport equipment

‘The dosign of the titers to harvest

brine shrimp naupli and metanaupliis

similar to that used to harvest raters —

though a larger mesh size of 125 um

for nauplii and 200 um for enriched

‘metanaupls used In addition, this sub-unit requires

{enough space inthe cold stororoom of

the hatchery to keep Artemia cysts

and enrichment diets in proper

Conaltions before thee utlsation

‘Space requirement calculation

The space occupied by the Artemia

culure tanks is determined by the

fexpoctod dally maximum consumption

cf bine shrimps naupli (is larval sh feeding) and enviened melanaupli

Calculations should therefore consider:

* the peak daily amount of naupi and enriched metanaupli consumed by fish,

+ the volume ofthe Artemia tans,

* the average output density of naupli and enriched metanaupli,

+ the numberof tanks fr incubation (Ti),

+ the number of tanks fr enviehment process (Te),

* the timing of both operations (28 hours incubation, 12 ar 24 hours for envichment),

‘The fst point depends on the total number and age of fish larvae being reared inthe larval nit and their feeding oqurements,

The second points a function ofthe average daly consumption and the necessary flexibly to cover

reduced needs during the intial and final rearing perods

The thrd point depends on the quay of Artomia batches: with an incubation density of 26 gl a

‘conservative estimate would be an etpot f 480 000 naupfil for low quality cyats (fo be enriched as metanaupi) and 650 000 nauplil for high quay cysts The stocking density for naupli envichment is

300 000 naupllI, and the minimum survival expected ater 24 hours 90%

‘Warning: batches may vary widely in torms of efficiency, hatching time and hatching rate Example: If he peak demand per day is one bilion enviched melanaupli, we need to stock 1.1 bin

‘nauplil (wih an estimated survival rate of 90%) If we use cysis with an average output of 220 000 ‘api per of cyst incubated, the amount of cysts tobe incubated would be 5 kg Using an incubation rate of 25 g per tre a volume of 2000 litres is require, hat may be provided by asingl 2 000 tank, fortwo 1 0001 tanks Twenty four hours later, a further 3700 res of tank vlume would be required to

‘enrich the naupli (at an intial density of 300 000 naupliv), which means 2 tarks with a capacity of 2.0004 each

1.13 LARVAL REARING UNIT

“The rearing ofthe fish larval stages takes place ina fargo room, usually located not far rom the Ive feed production unit to facttate the transport of algae, rofers and brine shrimp naupli, The same room

shuld have enough space to house the folowing ancillary facies:

the tanks where eggs are incubated

‘an area where all the equipment requied in this room could be routinely cleaned, disinfected and Sloe,

the insulated tanks forthe cold storage of ve feed (eniched roles, brine shrimp nauplii and

‘enriched metanaupi)

Windows are not necessary s9 lanal fearing requires controlled light conaitions, but they ean be insaled to fenew the air inside the room and to reduce humidty Fan extracts can be sed as well Floor and walls should be tie to secure proper hygienic conditions and to facto frequent cleaning Since fst harvest the tanks are emptied, an adequate drainage system is required It

‘should be made with sereened channels Under the floc, which should have 2 slope of atleast 2%

‘when a water recitculaton system is used, enough floorspace close to the larval rearing tanks should

‘be planned to place campenents such as mechanical and biological fiters, pumps, serlzers and heatingleooing devices I normal drains can be placed unde the flocs it should be borne in mind that

this cannot be done forthe gutters conveying water fo the biological iter These gutters should be placed above floor level to prevent tor toxic chemicals, such as asinfoctans used to wash the floor, from entering Ino the recirculation system

Production facl

Egg incubation can take place either in the langl rearing tanks orn tanks designed for this purpose

‘usally round tanks with conical bottom due to of thei near optimal water creuaton Ther capacity

‘anges between 100 and 5001 since a small vlume allows fora higher water exchange ale and makes the harvest of newly hatched larvae easier As €99 Incubation lasts a few days only, the tanks can be

se for several hatching cycles Materials used are libregass or paste ensuring a smooth inner side

to avoid damage to eggs and larvae Due tothe relatively small amounts of water requiod, the wator supply system for these tanks preferably of the flow-through type, Le new water is added continuously and not recirculated

For the larval rearing of Mesteranean fish, diferent tank designs have been adopted: high round tanks

‘with conical bottom, ow crula tanks with a sighty concave Bottom or fat-bottomes square tanks On

‘verage their capacty ranges ffom 2 to 12 Mm They are most commonly made of fibreglass, but reinforced concrete, PE and PVC are also used

“Thọ shape and size of larval tanks are decided on the basis of a numberof considerations:

1 management efficiency

* the larval population shouldbe easily visible throughout the whole water volume: + the tank bottom should be easiy accessible for daly cleaning; a white colour faiitates a beter detection of di

* cleaning should be a simple and not ime-consuming routine:

+ the feed should be evenly cistibute: + round tank walls can be painted in black to facitate food panicles detection by fish larvae + easy replacement of screened outlets;

+ simple outlet construcon for access and service:

+ minimum stress to ish at harvest:

2, water erovation * absence of dead zones and related negative consequences (anoxia,

‘ammonia build-up, le)

+ optimization ofthe aeratlon pator

‘concentration of seed wastes in afew ‘areas ofthe tank attom to allow fora

faster and move efficient cleaning

+ opimal swimming behaviour offi

* opimal isibufon of food partite; 1 fan

3, economies: materia; * ương lexl munbay dkudng | bad | —”

* transport problems in case of prefabricated tanks:

+ optimal use of space:

+ simpllied desig of suppor systems (water circulation, air supply, power ° ; + Ị | supply illumination) † i

+ manpower requrement for thei

4 risk prevention * alarge number of smaller tanks ofrs a

fetta, protection assinet disease

‘Among Mediterranean hatcheries, small tanks by larger fat tanks (5 t0 10 mas they simplify considerably the overall design ofthe larval unit and wih a conical bottom are being progressively replaced

reduce sta labour On the other Nand, the use ot arge tanks may imply a higher rskin case of disease

‘outbreaks,

‘According to their shape, number and avalable space, tanks are arranged eter in groups orn single

‘or double rows, In eer case, sta should have access to atleast 75% of ther perimeter The space

between rows or groups shouldbe wide encugh (0.8 fo 1.5 m) to permit he use of roleys fr ive food

—

‘Support systems

‘Asa ule, the larval rearing unit requis acean-qualiy seawater at a fay constant temperature, inthe

‘ange of 16 0 20°C In the wil, reproduction of seabass and githead seabream takes place during the

old season, with lower seawater temperatures but larval growth is also slower Ita reliable natural

source of warm seawater is avallable or when the diference in temperature wih the extemal

fenvronment is acceptable, the larval sector is equipped wih aflowthrough cuit the water that

eters the tanks isnot recyced a the outlet, but discharged

In the other cases, cold raw seawater has to be heated To reduce the heating costs, reiculation

systems ae included, which most of he rearing waters recycled instead of being replaced by new

water Recycing sysioms require a bitter where toxle ammonia (product of fh metabolism) |S Diologicaly oxidised into the safer nites and nitrates, PVC pipes are ulised for water supply and

‘drainage The circuit design should aveid sharp bends and be as simple as possible to avoid large

pressure losses and the establishment of dead zones where seciments and bacteria could accumulate

‘Components shouldbe assembled by means o! fast ons and boted flanges to allow easy dismanting

{or cleaning and sorvco operations According tothe water supply systom, Le by gravy orby pumping, PVC pipes should be NPS 0” NP10 respectively to stand fernt pressure loves

Each tank should be equipped with an independent inlat placed on the tank rim; a ball valve should be

used to aust its flow according the larval rearing requirements The angle at which water enters the

tank wll depend on tank desigh and on the age ofthe fish population

Light intensity should be maintained in the range of 800-3 000 lux at the water surface when both

choad seabream and seabass are reared Ahalogen lamp placed over each tank works well and has,

2 low electricity consumption, AS a general rule, 20W for every 1.5 m of water surface should be

pote

>Œ)

sufcient, Lamps should be controled by a timeddimmer switch to produce a twiight fect and to reduce stress winenights are turned on and

of

A sorvce light that would not

‘stub fish may also be useful

in case of emergencies Large windows should be avoided to provent direct sunight from Feaching the larval rearing tanks, a8 ti a souree of grat stress fr fish larvae,

To pravent excessive turbulence, the aeration in fish larval rearing tanks

‘shouldbe very gen, with an air flow of up to 60iminute

‘Tho aeration, n synergy with water croulation and tank shape, shoul provide an even distroution of

‘oxygen and food particles as wall as gontle currents to alow fish larvae to develop ther swinming behaviour Aquarium plastic nese valves, or metal clamps (much mor pensive), can be used for airflow regulation Tap water shouldbe at hand wih afew delivery pons and a wash-basin fr clearing purposes

‘Space requirements

Incubation tanks

‘The water volume required fo incubate eggs is based

fon the folowing criteria, whch are val for both fish

species:

* maximum density of fish eggs: 15 0008,

* minimum acceptable rate of abl larvae: 75%,

* number of viable larvae atthe start ofeach larval .yce (see below),

+ Unit volume of incubation tanks,

Larval rearing tanks

“The water volume necessary for lava rearing is

‘dotarmined on the basis ofthe folowing enter:

+ umber of fsh species tobe reared,

+ amount of ngeings requited per species and production yet,

‘final larval density and average survival inthe larval rearing sector,

+ fina larval donsty and average survival inthe weaning sector,

“The last two points also depend on a number of

‘variables such as: tank shape, rearing method, stall

NT ace _shapa and Water management

“The following indications on stocking densities forthe hatchery and will have tobe adjusted ator tho fst production eyctes, two species can be used forthe ina als & Githesd seabream

+ iil stocking density inthe larval unit 200 newly hatched larva per ite,

+ final stocking dens Inthe larval unt 60 fry per tive (survival ate 30%),

+ iil stocking dens inthe weaning unit: 20 try per ite,

* final stocking density inthe weaning unit: 6 ty per live (sunvival rate 90% - density is diferent because inthis sector sh are graded several times

—

I stocking density inthe larval unit: 200 hatched larvae per live,

* final stocking density inthe larval unt 100 ty per le (survival rate 50%),

+ inal stocking density inthe weaning unit: 20 try pe tre,

+ inal stocking density inthe weaning unit: 8 ry per live (survival rate 80% - density is diferent because inthis sector fish are graded several times) 1.14 WEANING UNIT

‘The weaning unit is essentialy organised as the lanal rearing unit Only the difrences between the

‘wo units are indicated below

‘Due to the larger ize ofthe rearing tanks and tothe lower inal stocking densities, the weaning sector quires much more space Iti usually aGjacent tothe larval rearing unit to facltate the transfer of đen

Windows can be installed to reduce

tha high degree of humisily and to ew the alr AS fish grow, they

should be gradually adapted to the

natural light, although avoiding rect

Sunlight on the tanks

‘The drainage systom is also larger

than inthe larval rearing uni Large

doors are recommended to move

‘equipment as wel as large containers

fon wheels caryng fingerings at the

tend of he weaning cycle, Preferably

tarmac road should run along one side of the bulcing to give easy access to

lorties used for the delivery of

8quipment and for transport of

‘The weaning tanks are characterised

by a larger size than the larval tanks

and can be of diferent shapes The

models most widely adopted by Mediteranean hatcheries are round

‘tanks with flat or sighty concave bottom and the raceway tank, On average, thee capacity ranges from 10 to 20 mm, as larger volumes may limit he flexibly requited for frequent fish grading, which is @ routine practice in weaning They are usualy made of fibreglass and eiforced concrete, But masonry, plastic shoots and rigid PVC aro also ulized

“The racoway design isa rectangular tank through which the water curont ows from te int, placed

at one end, tothe outlet that is placed at the opposite end lis hycrauc efciency is satisfactory,

‘provided that dead zones and straitcaton are avoided by adjusting the water iniow and aeration TO prevent circular eddies which could accumulate waste and debris inthe cont, the length ()/ width lơ) Tato should net be lower than 6 For easy management, water depth is usually Kept at one mare,

‘whereas the bottom slope is 1-2%,

(Often a PVC pipe is used as tank outlet because ofthe easiness in ins

‘900d solution is also a monk vith the sets of grooves to

fon and use Another very + prevent fish trom escaping (inner screen),

* evacuate the botlom water and sediments by adjusting slabs (contal sot of grooves),

‘+ keap the desired water lave (outer set of slabs)

.As the outlet covers the enti section ofthe tank, this typeof outlet is more efficient (ue toa reduced logging risk and its easy replacement than a central or terminal dain wth a screened pipe Waste

‘removal isa function ofthe water speed linked to renewal rate), and ofthe fsh biomass, since a high

‘number of fish wil stir up more sediments The shape ofthe raceway is aso ideal to harvest and grado

‘ish, and at he same time makes good use of the available floor space, whereas circular tanks waste aout 30% of the avalabe room area,

‘Suppor systems

The waler supply systom is similar Yo the larval rearing unit but bigger When a recycing systom is Present, an independent water circuit supplying treated, but not heated, seawater Is advisable to

increase management tlexily

‘The light intensity should be about 1 000 lux and the weaning unt does not requice the twilight elfect escrived in the larval rearing unt Fluorescent tubes are placed over each tank and a power of 20W

‘very 8m of water susace is usualy suficion

This unit requires a fow addtional power sockets to connect the vacuum cleaner used daly for the removal of the waste accumulated on the tank botlom A low votage line is also required to dive the

‘automatic feeders used forthe fst tie in this unt

‘Space requirement calculations

“The inalshf rom lve to atfeal ood is achieved inthe weaning unt, Combining an increased water renewal and injection of pure oxygen inthe tanks, this secton may reach ai sh biomass as high

as 20 kgin? At an indviual size of 2-8 grams, ths means a final density of 6 to 10 000 fingerings which should be used as a general indication for space requirement calculation,

1-18 SUPPORT UNITS

Pumping station

“The size ofthe pumping station depends an the quantiy of water needed and on the type, dimensions, and number of pumps installed, including stane-by units The desception of he size calculations forthe pumping station can be found inthe engineering section of his volume (Part 2)

‘The site where the pumping stain isto be located shouldbe easly aocessbe, to simply transport of pumps and other equipment Moreover the pumping station should be located as close as possibie to

the hatchery ofacitate constant survellance

‘The pumping station, even when submersible pumps are used, shouldbe protected a least by a shes

‘and should have good lighting, to faciate maintenance and eventual reps Auxiary electrical Sockets shoul! be provided and, iat all possible, freshwater should be avallabl lo facitate routine

‘maintenance work the puring sation i lacated nea the seashore it should be protected, not only

‘against wave action, but also against salty sea spray

Horizontal pumps are normaly placed inside a smal oom, gether wit he electrical control an alarm Panels, to ensure a degre of protection against almospheric agents Tis room usually aso includes ' small workshop where the most commonly used tools for pump maintenance and repair are permanently store,

‘The need for a possible urgent intervention should be contemplated

in the design stage When large submersible oF vertical pumps are Used, the space where they are housed should be large enough to low technical stat to work safely fon the pumps without having lo Femove them from thei seal Whenever the weight of a pump prevents direct handling, the pumping station shodld be equpped with an arm and a singh to it the

pumps and to place them on a oncrete platform This platform should be but near the pump seat, for routine maintenance ‘case of serous damage, or repairs in

Seawater wells

‘Nong sandy shores, wells dug in the beach are frequently used On the postive ide these walls supply

‘tered water, often ata constant temperature, However, serious problems can aise if they are over

‘exploited because they tend ta clog the sand bed easly by sucking small parcies when pumping Such els are sultable when water demand in the hatchery is relatvely low Even in that case, and

‘depending on the size ofthe sand parc, they wil have to be abandoned sooner or later and new

‘wale wil have to be dug

ls in rocky shores or deep enough to reach a stable but permeable rocky ground are usually very

‘ticient and representa permanent Solon, even i their ater may not be of such a good quality as

‘hat obtained trom sandy wells Well water oflen needs tratement belore use, because of low oxygen

‘content or because of organic or inarganse pollution Facies for this purpose shouldbe considered Pumping station to hatchery connection and wastewater treatment

‘This section refers to the pipes supplying seawater tothe hatchery Pipe length and dlameter depends

‘on the location ofthe pumping staon wih respect othe hatchery buildings and also depends on the

‘20 of Its compononts (pipelines an treatment systoms) It has 10 be designed in relation to the

‘quantity of water to be supped

‘Apipatine is nomally used when water is distibuted under pressure tis betero place It under ground level, to cross farm roads without hampering vehicle or uoley circulation Since pipelines require peridical mainlnance an cleaning to remave sand and fouling, they cannat be completely buried i

's best o place them ina trench, wel-protected by grds or concrete slabs

Water sistributed under pressure can be fitered tough pressure Sand ftes on arival atthe hatchery These ters should include an automatic backwash system to Increase fitrabon efficiency and to reduce maintenance,

her than the al water discharging Plt, outside the farm,

‘The waste water treatment should

be cartied out along the ascharge channel It should be based on fitation systems using gravity to move the water rather than pressurized systems The most Sutable sysiom le the drum fier, hich is abet retain a large amount of he insoluble organic load (suspended solids) normally present

in ch farm efuent Where space isnot a problem the wastewater produced by the hatchery can be Circulated through a settlement tank In the case of a high organic load, the water passed through @

‘tum fiter or sedimentation tank can be diected Into one or more earthen ponds were the remaining

‘organic wastes are biologically degraded (lagooning system) This system, however, may requ large surfaces depending on the quantity of wastewater produced and tothe quantiyiype of waste to be twoated

Boiler room

‘This unt houses the lr and water heating systom The capacity of the systoms and therefore the size

of te room depends on the local climatic conditions Daily requirements are determined by the Giflerence between external temperatures (aihwater) and those to be maintained inthe working areas,

‘ang by the waterat volumes of te various rearing unis

The room should contain two boilers working in rotation, with each of them having sufficient capacty to provide the calories required curing the peak period ofthe hatchery operations The double system prevents interruptions in heated water and alr supply incase of far of one boiler Heating systems are usualy based on tuo olor natural gas burners From th bole room, two separate stoel pipelines feed the heat exchangers for seawater eating and the air healers Each pipeline should be properly Inulata to avols hea losses,

Tho boler room should be bull according 10 nationabocl safety rules, which may establish its rinimum size, the aeration requirements and, due tothe presence of fuel reservoirs, the minimum stance between bole and surrounding buildings Auxiliary electrical outlets should be provided for maintenance and eventually shouldbe placed ouside the bol room fr safety reasons

Wile planning the location of this unit, its important to remember that fuel ol or gas tanks should be next toa road large enough to allow tucks to manoouve

‘When designing the power network,

is important to bear in mind the peak lectical demand generated when a engines stat, which could be four to Six times higher than their normal consumption Delay switches should

be installed to stop all the electlcal engines and appliances starting simultaneously Prony should be {ven to essential equipment, suchas pumps and aerators In order to festimate the size of the emergency generator, it wil be necessary to identity the equipment that plays a

“The room housing the generators) hud be located outside the hatchery lt should be soundgroef lo reduce the noise caused by the diese! engine ofthe generator Construction standards should respect the same natonalocal safety us a in the case o the ballor room, sinco fuels also used inthis room

Workshop

“This isthe unit where most ofthe hatchery equipment maintenance and repair takes place This unit

‘Should guarantee that everthing runs smoothly when dealing both with routine maintenance and

‘emergencies hat may happen during the production season,

tts design flows the rules normaly applied when buiding an industrial workshop a relatively large fee

“pace in the centre ofthe room equipped wih awineh and strong benches around ito fcitate work even ‘on large and heavy equipment This central space shouldbe large enough to allow the entrance of smal vehicles tke vactors oF pickups bringing fargo pieces of equipment to be soviced A sores of metal benches are placed along the walls, equipped wi all the necessary toot-noders A storeroom is usualy

‘tached to the workshop 1o stock spare pars The warkshep should be adequately iluminated, both inside and outside kt should also be connected fo he freshwater and eleciicty (220 and 380V) circus

Feed store

‘This unit, which ina large fish farm occupies a lage storehouse, does not require much space in @ hatchery’ Only a few hunted klograms of dry feed for larvae and fry are routinely kept instock, even uring ful production periods The feed should be located ina dn clean room, protected against rodents and easily accessible to hand.rolieys