Water reuse in an integrated system with fishes, sedimentation, oysters and macroalgae

Abstract Intensive culture effluents have high levels of dissolved nutrients, mainly ammonia, as well as suspended solids. The objective of this work was to use integrated aquaculture with fishes, sedimentation, oysters and macroalgae to improve water quality from a salt water tilapia culture. The fish effluent was distributed in three sedimentation aquariums for a period of 24 h. Then, the water was transferred to three oysters aquariums for another 24 h period. Later, the oyster water was transferred to three macroalgae aquariums for another 24 h. Finally, macroalgae water returned to the fish aquariums. After two weeks, water turbidity and ammonia, nitrate, nitrite and phosphate concentrations were determined daily. The system was efficient to significantly reduce turbidity and ammonia and phosphate water levels. Nitrate and nitrite levels were only reduced after maturation of the sedimentation aquariums.