The UVI Tilapia Nursery is a recirculating aquaculture system capable of producing 100,000 50-gram tilapia fingerlings each year.
The tilapia nursery consists of 12 rearing tanks, filter tanks, water circulating pump and regenerative air blower.
Fry are stocked at 1,000/m2, 2,000 fish/tank. One tank is harvested and restocked each week.
Fry are stocked at 1-g and reared to 50-g in a 12 weeks.
Solid waste is removed by a drum filter and dissolved nitrogen waste is removed in a fluidized bead media filter.
Considerations for nursery management
- Water flow/exchange rate – 1x per hour
- A faster flow rate will remove waste faster and provide for a cleaner growing environment
- But will require more energy to be used for swimming against the current
- Will require higher electricity consumption to pump water faster.
- A slower flow rate will require less swimming and energy use by the fish
- But water quality will be less than optimal for fish health and growth
- Will lower the electrical requirements of the water pump
- Feed ad libitum 4 X each day for 30 minutes per feeding
- Ad libitum feeding allows for precise rationing of daily feed intake and best feed conversion
- But requires more labor and time
- Fixed rate feeding saves time
- But can lead to underfed fish and slow growth
- Can lead to overfed tanks and wasted feed
- Stock once – harvest once
- Tanks should be stocked at recommended rate and harvested completely 12 weeks later
- Stock splitting
- Stresses fish during transfer
- Fish growth slows as peak biomass is reached before splitting