Growth of Pangasius hypophthalmus in sewage treated water

Treated sewage water constitutes a sustainable water resource that has been used for aquaculture. The suitability of sewage treated water for Pangasius hypophthalmus (Sauvage, 1878) was estimated during the present study in terms of growth parameters. P. hypophthalmus was cultured under three treatment groups: freshwater, sewage treated water without feed and with feed. The growth parameters of P. hypophthalmus in cultured in freshwater, sewage treated water with feed and without feed revealed higher weight (40.86 g), length (16.88 cm), weight gain (724.07 g), average daily weight gain (0.66 g/ day), biomass (817.20 g), percent increment in weight (1021.29%), percent increment in length (106.55%), specific growth rate (1.17%) and survival (100%) for fishes in sewage treated water with feed as compared to the other two treatments. Despite the absence of any external feeding, the fishes were able to survive in sewage treated water without feed as it is rich in nutrients, organic matter, micro-organism etc. The growth (weight, length) of P. hypophthalmus showed significant positive correlation with temperature (26.39°C), conductivity (2.45 ms/cm), total dissolved solids (618.95 ppm), dissolved oxygen (6.10 mg/l), pH (7.86), hardness (283.30 mg/l) and salinity (1.36 ppt) of sewage treated water, however, ammonia (0.58 mg/l), nitrite (0.09 mg/l) and alkalinity (198.80 mg/l) had no correlation.