Evaluation of the effectiveness of a biological filter in improving water quality in commercial fish farming

Resumo

The objective was to evaluate the efficiency of using biological filters in commercial fish farming on the physical-chemical parameters of the water. The system was built and tested in a commercial fish farm in a tank containing 69,137.1 L of water. The filter system was composed of settling tanks, root zones, a media area, equalizer, and probiotic tank. The plants used were Mururu (Eichornia crassipes), Cattail (Typha domingensis), and duckweed (Lemna minor). The physicochemical analyses corresponded to the following parameters: pH, dissolved O2, hardness and total alkalinity, chlorides, conductivity, total dissolved solids, turbidity, nitrate, nitrite, aluminum, manganese, ammonia N, orthophosphate, sulfide, zinc, residual chlorine, chromium, aluminum, total phosphorus, and iron. Statistical differences (P<0.05) were observed for the variables: pH, temperature, dissolved O2, total hardness, turbidity, nitrate, nitrite, ammonia N, residual chlorine, chloride, conductivity, and phosphorus, demonstrating the efficiency of the biological filter for improving water quality. Therefore, the biological filter promoted the expected benefits, improving the water quality in the commercial pond.