High stocking densities in the larviculture of Colossoma macropomum in a recirculating aquaculture system: Performance, survival and economic viability

This study investigated the use of high stocking densities and in the larviculture of Colossoma macropomum in a recirculating aquaculture system (RAS), including an economic analysis. Densities of 60 (D-60), 120 (D-120) and 180 (D-180) larvae L-1 were tested, with four replicates each. The larvae were fed with Artemia nauplii during the first 15 days of cultivation and with ration from the 16th to the 25th day, through the direct exchange of commercial diet for live food. Ammonia was affected by stocking density with the highest value for D-180 (P < 0.05). Performance and survival were not affected by stocking density throughout the experiment (P > 0.05). The number of animals produced at the end of the larviculture increased with the increase in density (P < 0.05). At the end of larviculture, animals classified as medium predominated in D-60 and D-120 (P < 0.05), while there was no difference between small and medium classes in D-180 (P > 0.05). Net revenue was negative for treatment D-60, leading to a financial loss in production, while treatment D-180 had the best net revenue. In conclusion, intensive larviculture of C. macropomum can be carried out in RAS with up to 180 larvae L-1, with good results in terms of performance and survival, as well as good indicators of economic and financial viability.