Carbonaceous biochemical oxygen demand and nitrification oxygen demand of the effluents of Penaeus monodon culture ponds

Abstract

Five-day carbonaceous biochemical oxygen demand (CBOD₅) of Penaeus monodon pond effluents varied between 9.3 and 34.0 mg/I and ultimate carbonaceous BOD of the effluent varied between 10.7 and 42.0 mg/I. CBOD₅ of the effluents were 51-2 to 86.9 percent of ultimate CBOD. Rate of biochemical oxidation (k) of shrimp pond effluents varied between 0.06 and 0.18 per day with an average k value of 0.12. Nitrification oxygen demand of shrimp pond effluents varied between 0 and 1.0 mg/I at 5 days, 0.4 and 22.9 mg/I at 10 days and 13.4 and 38.2 mg/I at 20 days. Combined oxygen demand of shrimp pond effluents varied between 9.3 and 34.0 mg/I at 5 days, 20.4 and 64.6 mg/I at 10 day, and 28.0 and 28.0 and 80.0 mg/I at 20 days. At 20 days, nitrification oxygen demand were 29.0 to 61.8 percent of combined oxygen demand. Results of laboratory scale investigation indicated that aeration can significantly increase reduction rate of BOD₅ of shrimp pond effluents.