The mean water temperature was 28 °C (ranged from 26 to 29 °C) during the study. Mean dissolved oxygen ranged from 7.4 to 10.7 mg l−1 and mean pH ranged from 8.1 to 8.2. Total hardness (as CaCO3) and total alkalinity (as CaCO3) of the hatchery water was 150 and 130 mg l−1, respectively.