Parameters Stocking density@ 7,500/ha Stocking density@ 10, 000/ha Stocking density@ 12, 500/ha pH 8.0a 7.6a,b 7.3b Dissolved oxygen (mg/l) 5.5a 5.0a 5.0a Ammonium  nitrogen NH4-N (mg/l) 0.04a 0.08b 0.12c Nitrite nitrogen NO2-N (mg/l) 0.03a 0.04a 0.08b Nitrate nitrogen NO3-N (mg/l) 0.10a 0.14a 0.20b Orthophosphate PO4-P (mg/l) 0.02a 0.02a 0.02a Total Phospahte (mg/l) 0.03a 0.03a 0.05a Dissolved organic carbon DOC (mg/l) 1.8a 2.8b 4.0c Total  alkalinity (mg/l as CaCO3) 140a 120a 100a Turbidity (cm) 18a 16a,b 12b Chlorophyll a (mg/l) 0.20a 0.30b 0.40c

Table 4: Average water quality parameters in the polyculture of Indian major carps. Values followed by the same superscript in a row are not significantly different at the 0.05 levels

Goto home»