The associated use of artificial substrates and biofloc system in the intensive culture of Macrobrachium rosenbergii

An indoor trial was conducted for 64 days to evaluate the individual and combined effects of artificial substrates and production system (BFT vs. traditional) on water quality, plankton composition, and the growth of Macrobrachium rosenbergii . The following treatments were established, all with three repetitions: traditional production system without substrate (TPS), traditional production system with substrate (TPS-S), biofloc system without substrate (BFT), and biofloc system with substrate (BFT-S). The prawns (4.13 ± 0.04 g) were stocked at a density of 41 individuals m -2 . Polyethylene screens were used as artificial substrates in the proportion of 252% of the tank bottom area. TPS treatments received water changes of 10% of the experimental unit volume per week. Molasses was used in the BFT treatments at a carbon:nitrogen ratio of 6:1. The presence of substrates in both systems improved water quality, maintaining ammonia and nitrite levels within the recommended range. The growth in TPS and TPS-S were higher than BFT and BFT-S. Survival and yield were influenced by substrates and BFT, being superior in BFT-S. The presence of substrates allowed phytoperiphyton growth. The BFT-S had a higher abundance of protozoa and rotifers than the TPS and TPS-S, due to the operational characteristics of the system. The use of BFT with artificial substrates is recommended for the intensive culture of M. rosenbergii , as it improves water quality, survival, yield, and promotes a higher abundance of protozoa and rotifers; however, these findings are based on a 64-day indoor trial and require validation at commercial scale. • Artificial substrates in the culture medium improved water quality. • The artificial substrates allowed the growth of phytoperiphyton. • Prawn growth was higher in the traditional system than in the biofloc system.