The African catfish (Clarias gariepinus) is one of most popular freshwater fish and have a high demand in Malaysia. However, during rearing time, they show an inconsistent on
growth and survival rate because stocking density. For this experiment, the C. gariepinus, 30 days after hatching (AH) were taken from the hatchery of Borneo Marine Research
Institute (IPMB). C.gariepinus was kept in nine aquariums at low, medium and high density (5/L, 10/L and 15/L). Length was measured to the nearest centimeter and weight to the nearest gram. The juvenile were then assigned at random to nine aquariums (7L aquarium). The juvenile were fed 3 times daily using commercial pellet at 3% of total body weight for each treatment. The juvenile were measured in term of total length and body weight and survival were measured every 5 days for 1 month. It was found that the growth rate were similar for all stocking density tested. The survival rate was significantly decreased with increasing stocking density, while swimming activity increases with increasing stocking density. Cannibalism which appears depend on
stocking density is higher in high density because of overcrowding and competition for space and food. Low density was the best result for rearing juvenile of C. gariepinus
which gives the highest survival rate and to avoid cannibalism. This study is can be used as a reference for fish producers to rear the juvenile fish especially in small scale production system.