BASIC SITE AND BUILDING REQUIREMENTS

Hatcheries need a reliable power supply, because continuous operation of the aeration system is essential. Even where public power supplies are reliable, you need a back-up generator. You may wish to generate all your own power but a back-up facility is still essential.

Power failure can quickly result in total stock mortality. You might think that your hatchery needs to be close to the nursery or grow-out pond locations where your product (postlarvae, referred to as PL) will be stocked. This is preferable but it is technically possible to transport PL for long distances, so it is not essential for technical reasons. Your water supplies - freshwater, seawater, brine, or made from artificial sea-salts - must have excellent quality, as described earlier in this manual. Site location for hatcheries operating recirculation systems is less dependent on the proximity of supplies of seawater or brine, because they minimize the quantities required. When artificial sea salts are used, only freshwater is needed on the site.

In tropical areas tanks in flow-through hatcheries can be situated in the open but you should provide, at the minimum, simple shading (palm fronds or a bamboo framework, for example) where there is a possibility of the water temperature rising too high. Water temperatures may also drop too low in tanks in the open air at certain times of the year for continuous operation. It is therefore better for you to house your tanks in a building, to make it easier for you to control temperature and light and to minimize the entry of insects

and dust. The roof and walls do not need to be permanent.

Figure 14c
Buildings are often rebuilt as the hatchery prospers but the structure remains simple (Thailand)

SOURCE: HASSANAI KONGKEO

Locally available materials are the best to use. Successful hatchery buildings in tropical areas are often very simple structures, which are easy to extend or re-locate (Figures 14a and 14b). If the hatchery is successful and business is good you can think of extending it and building something more permanent later (Figure 14c).
If you are building your hatchery in a temperate zone, a proper building becomes essential for temperature control and efficiency. No exact hatchery design is provided here, for the reasons explained earlier, but a general view of the interior of a flow-through hatchery is illustrated in Figure 15 and a simplified layout for this type of hatchery is shown in Figure 16. A diagram of a single- tank recirculation system is shown in Figure 17.