Effect of extreme high and low water pH on survival and behavioral changes of Labeo rohita
Author(s): Ajay Dasharathbhai Raval, Bipul Kumar Das, Shilpa Koley and Suchismita Saha
Abstract: A microcosm test was conducted to determine the lethal concentration for 50% mortality (LC50) after 96 hours. The LC50 at alkaline pH range was from pH 10.4 to pH 10.6. and the acidic range was from pH 4.4 to pH 4.6. Microcosm tests were carried out to investigate how water pH affects aquatic ecosystems. Range-finding test was performed on fish, Labeo rohita (weight 5.05±0.02, length 7±0.03 cm) with thirteen different pH values such as 4.0, 4.2, 4.4, 4.6, 4.8, 5.0, 7.0, 10.0, 10.2, 10.4, 10.6, 10.8, and 11.0. Fish were fed pelleted feed with 35% crude protein. The control group (pH 7.0) showed better survival. However, pH 4 and pH 10 showed very low survival. Mucus secretion reached elevated levels, and opercular movements increased at both pH 4 and 10. Furthermore, extremely high and low pH levels led to rapid jerking movements and frequent surfacing compared to the control (neutral) pH of 7.
