Applying Biofloc Technology in the Culture of Mugil cephalus in Subtropical Conditions: Effects on Water Quality and Growth Parameters

Mugil cephalus is an estuarine species that has been shown to acclimate to a diversity of environmental conditions being a good candidate to diversify aquaculture. The objective of this study was to evaluate the growth and water quality of M. cephalus juveniles in a biofloc technology system (BFT). Over a period of 87 days, mullet juveniles (117.36 ± 6.48 g) were reared in two experimental conditions: water exchange (control group) (50% three times a week) and BFT (C:N ratio of 15:1). M. cephalus juveniles were stocked at a density of 7.2 kg·m⁻³. Water quality parameters were monitored periodically. Fish were fed with a balanced artificial feed for marine fish (2% of the total biomass). The water quality parameters were similar between the treatments, with the exception of pH, alkalinity, TSS, and N-NO₃ (p < 0.05). Zootechnical parameters WG, DWG, BG, SGR, condition factor, and survival did not show significant differences (p > 0.05). The biomass gain was higher in BFT (p < 0.05). Water quality variables did not appear to influence mullet survival under culture conditions. Mullet is a species that can be reared in BFT without compromising productive performance and having a significant saving of water.