Bioconversion and Bioeconomic of Wastewater from Red Tilapia Aquaculture on the Aquaponics System as Source of Nutrient in Green Mustard Growth

Abstract

Fish farming activities produce large amounts of waste which is disposed to environment. It contains with ammonia and nitrite as toxic substances to aquatic biota. On the other hand, it also contains nitrate as macronutrient which is useful for vegetables. Aquaponics system provides multiple benefits, namely the production of fish and organic vegetables as by-products that potentially to be a source of income. The objectives of the research were to analyse physical-chemical quality of red tilapia aquaculture and cultivated vegetable in aquaponics system, fish farm wastewater discharge for vegetable cultivation, bioconversion of aquaculture wastewater for growing vegetable biomass, and the bioeconomic of the system. The physical-chemical quality from water body of the system were as followed pH= 7.2 7.6; Temperature = 27,4 28,0ºC ; EC = 392.0 400.0 µs/cm; TDS = 180.5 189.7 ; NO3= 3.751 5.266 mg.L-1. The total biomass of green mustard in recirculating system was 92.50 kg/tray unit and in dripping system was 138 kg/tray unit. In one harvest period of red tilapia, the production of green mustard biomass was 1,152.5 kg, with an economic value of IDR 8,643,750.00 and IDR 1,680,000.00 for the red tilapia biomass.