A Study on Water Quality in Relation to Length-weight Relationship and Relative Condition Factor of Two Fresh Water Fishes- Labeo Rohita and Oreochromis Niloticus in Krishna Raja Sagara Reservoir

Fish being the cheapest source of protein, the population explosion and economic pressure demands increase in fish yield. Since biotic and abiotic factors have influence on growth and well-being of fish, there is a need to continuously monitor the fish culture water bodies for physico-chemical water quality parameters and presence of pollutants. This work shows the allometric growth (cube rule) and well-being of two fresh water fishes Labeo rohita and Oreochromis niloticus and whether or not the deviation if any from cube rule is accompanied by altered water quality required for fish culture. This study reveals that majority of the physico-chemical water quality parameters namely temperature, pH, turbidity, conductivity, DO, BOD, TSS and phosphate were within the optimal range for fish culture, whereas nitrate levels were higher than the desired levels. These results indicate near normal growth and well-being in L. rohita as well as in O. niloticus in the prevailing environmental conditions in the KRS reservoir.