Abstract:
A study was conducted to compare the efficiency between the biodrum and the submerged biofilter used in the closed recirculating seawater system to culture the black tiger shrimp (Penaeus monodon) and seabass (Lates calcarifer) for 3 months. The recirculating system consisted of a circular rearing tank (7 diameter) with the operating capacity of 38 m3 (1 m depth) and a rectangular shaped concrete treatment tank with accommodated biofilter. Used seawater from rearing tank was treated in a separated biofilter tank. During operation, turn-over rate of the system was 4 times daily. During the culture of black tiger shrimp, both biofilters were able to regulated water quality parameters namely total ammonia, nitrite and nitrate to be within the normal ranges. Due to the low biomass of shrimp in this trial, it was unable compare the efficiency between two biofilters. The survival and growth rate of shrimp was 6.25%, 7.03% and 0.056 g/day, 0.051 g/day for biodrum and the submerged biofilter treatments, respectively. During the culture of sea bass, both biofilters were able to regulated water quality parameters namely total ammonia, nitrite and nitrate to be within the normal ranges. However, during total ammonia and nitrite of the submerge biofilter system were significantly higher (p<0.05) than those of the biodrum biofilter system. The survival and growth rate of seabass was 58.42%, 57.00% and 1.273 g/day, 1.228 g/day for biodrum and the submerged biofilter treatments, respectively.