World over Recirculatory aquaculture systems is considered as an advanced high efficient system that not only reduced the impact of aquaculture practices on environment but also helped in attaining an high yield on low resource utilization laying the path to sustainable future in aquaculture practices. There are still researches and innovations taking place in multiple fronts in order to make the practice more efficient and economical. For a market like India which is established globally but still emerging locally the subjects on which this investments are made plays a key role in identifying the returns.
There are very few species that maintain the steady demand throughout which can be considered commercial crop for Indian market conditions, to name Asian Seabass, Snake head murrel, Ilish (Tenualosa ilisha), Trout etc among some with high market values.
Major challenge in culture of these species as standalone subject is heterogeneity and cannibalism. At the earlier stage proper innovative nursery practices need to be followed that would avoid cannibalism and making sure of availability of feed for all fingerlings will help to minimize uneven sizes. This would help in increasing the high survival of fingerlings and on due course making them adaptability to confined culture practices.
Aquatick consultants has domesticated and built freshwater RAS facility including the multistage water filtration, nitrification and disinfection process as per Indian Farming conditions.The facility being established at Madhavaram is designed to accommodate for nursery and grow out culture of Seabass.Nursery consists of a 70 m3 - 1 tank (D Edged Raceway) which can hold a total stocking of up to 30,000 seeds. Major challenge in this setup is to achieve an high survival rate of 60 Percentage before these fingerlings are transported to respective grow out ponds that are designated as per the sizes of juvenile. Even at a survival rate of 30 Percentage (half of expected) grow out will be having juveniles sufficient for a 100 m3 (3 Circular Tanks) system at harvest stocking density of 50 kg/m3.
As culture process for nursery and grow out are maintained separately the duration of culture period can be distributed in a way that the regular harvest period at marketable table sizes can be reduced by up to 5 months. As juveniles in grow out ponds are evenly distributed based on the size Cannibalism will be reduced. Expected harvest in one such system is 5 Tons per harvest and can be increased based on changing aeration and nitrification apparatus.