Influence of Temperature and pH on Critical Water Quality Parameters of Laboratory reared Culture Media of the Economically Important Heteroclarias Fish Fingerlings

Abstract

The attainment of species-specific conducive water quality environment is crucial to optimum production of fishes in captivity. This need therefore, informed the study of relationships between temperature, pH, and physicochemical parameters of Heteroclarias fingerlings under laboratory conditions. The fingerlings were raised at water temperature regime (Ambient (26.91oC), 28.00, 30.00 and 32.00oC); and pH of 5.00, 7.00 (i.e. ambient), 9.00 and 11.00. The water quality parameters (Dissolved Oxygen (DO); Biochemical Oxygen Demand (BOD); Ammonia; and Conductivity), of fish culture media were monitored weekly for three months. The results indicated that water temperature had no significant (P>0.05) effect on Ammonia concentration (range = 0.15 – 0.17mg/l) and pH condition (range = 6.78 at 26.91oC, to 6.95 at 28.00oC) of the culture media. Water temperature significantly (P<0.05) reduced DO from 6.16±0.91mg/l at 26.91oC, to < 5.00mg/l at temperatures above 28.00oC; but no significant difference in BOD at all temperatures levels. Conductivity increased significantly with rising temperature above the ambient condition (range = 251.02±59.73μS/cm at 26.91oC to 352.89±79.09μS/cm at 28.00oC). pH had no significant effects on the parameters at pH conditions tested; temperature, DO, BOD, and Ammonia. With the exception of significant difference in conductivity (P<0.05) of rearing media of Heteroclarias (range = 304.42±47.20μS/cm at pH 7.00, to 380.94±38.40 μS/cm at pH 9.00). pH 11.00 could not support survival of the fingerlings. The findings of this study have provided useful information for effective water quality management in artificial culturing of the fish Heteroclarias.