Optimizing Water Flow Rate to Improve Growth, Feed Efficiency, and Stress Response in Sustainable Hemibagrus nemurus Farming

The Asian red tail catfish (Hemibagrus nemurus) is a native fish from the Indonesian freshwater. The fish is targeted as a potential fisheries commodity; thus, its farming technology has been actively developed. This work aimed to investigate the water flow rate's effects on the growth performance, feed efficiency, and stress response of H. nemurus. The fish seed (an average length of 1.64± 0.18cm and an average weight of 0.06± 0.004g/ fish) was obtained from the spawning of selected broodstock weighing about 1.5kg/ fish. A 500L round fiberglass was used as the experimental container, filled with 150L of water. Each pond contained 1.500 fish seeds, randomly collected from an acclimatization container. They were daily fed at 10% of their total biomass thrice. The fish rearing was conducted at a water flow rate of 10, 20, and 30cm/ s. The following parameters were recorded: absolute length, absolute weight, specific growth rate, protein retention, survival rate, cannibalism, and length–weight relationship. The water flow rate has been shown to significantly improve water quality in aquaculture systems. Specifically, a flow rate of 20cm/ s produced the most favorable conditions for the rearing of H. nemurus, resulting in the highest specific growth rate (5.02%), the highest survival rate (47.81%), and the best feed efficiency (85.69%). These findings indicate that maintaining a water flow rate of 20cm/ s is optimal for promoting the health and growth of H. nemurus in aquaculture settings.