Minimum Requirement to Improve Quality before Discharging from Hybrid Red Tilapia Intensive Cage-Culture in Earthen Ponds to the Environment

This study determined a practical method to reduce environmental pollution by wastewater from fish ponds. Water quality in three hybrid red tilapia ponds (0.24 ha) was examined before and during harvest at five water depths of 10, 20, 50, 100, 150 cm, as well the surface pond bottom. All samples were analyzed for BOD, TN, TP, TAN, TS, TSS, SS, with results compared Thailand control standard freshwater aquaculture effluent. parameters seven showed statistical significance (p<0.05) that increased depth. Degradation highest bottom 50 cm pond. Limiting drainage depth achieved tilting pipe, resulting effluent met all parameter standards. At remaining drained using pump, failed meet required When this allowed settle 24 h, TSS reduced 21.06%, 2.42%, 11.68%, 5.47%, 43.36% full values, respectively. Results suggested sedimentation technique requiring smaller area pollution.