Viable approach for pisciculture in sewage water - A review

Sewage water, treated or untreated, municipal or otherwise, contains potential nutritional resources. Chemically it is difficult as well as uneconomical to extract them. These can be eaten by fish directly or through food chains, and thus can be converted to animal protein naturally. Pisciculture today is mainly dependent upon fish- meal, which is a protein source. This fish- meal is expensive and not readily available at all places. Fish and algae can extract the protein and nutrients from the sewage water and in the process also treat the sewage water. In Kolkata the waste-water aquaculture system receives about 55,000 cumec of untreated sewage per day and an estimated production of Carp and Tilapia is seven tones per hectare (East Kolkata wetlands Management 2007). The main potential of wastewater-fed aquaculture and its major advantage over conventional wastewater treatment is the large diversity of marketable products and therefore broad possibilities of income generation. The combination of the two income generating options (wastewater treatment and biomass production) is a very interesting feature.