Rearing of fat snook, Centropomus parallelus, through a marine recirculating system

Resumen

Recirculating systems present several advantages in relation to the conventional production systems in aquaculture. Studies of the effect of stocking density on the growth of fat snook, Centropomus parallelus, were conducted in a recirculation aquaculture system in Ubatuba, northern coast of São Paulo State. Juveniles weighing 32.53 ± 6.54 g were stocked in densities of 7 and 20 fishes/m3 and appraised for 75 days. The fish were fed with commercial diet with 40% of crude protein, supplied ad libitum four times a day. The environmental variables (water temperature, oxygen level, salinity, ammonia, nitrite and nitrate were within the parameter values deemed ideal for this species. Survival rates were not different (p>0.05) between the treatments. The mean final weights, final biomass, specific growth rate and earnings of daily gain weight indicate that the treatment of higher density was (p<0.05) superior to low density. The recirculating aquaculture system proposed in this study was shown to be appropriate for production of C. parallelus. The stocking density of 20 fish.m-3 proved to be more productive than that of 7 fish.m-3) and it should be recommended as reference in new studies in recirculation systems with this species.