The Effect of Different Stocking Densities on Growth, Production and Survival rate of Pangas (Pangasius hypophthalmus) Fish in Cemented Tanks at Fish Hatchery Chilya Thatta, Sindh-Pakistan.

The effect of stocking density on growth performance, production and survival of Pangas, Pangasius hypophthalmus were evaluated in cemented tanks. Fry of Pangas (1.52 ± 0.03 cm in length and 1.08 ± 0.02 g in weight) respectively were stocked into cemented tanks measuring 15 x 6 x 3 ft. Three treatments with two replicates were used: T1- 100; T2-150 and T3-200 fry/ tank. Pangas fry were fed twice daily with formulated feed 35 % protein at 10%, 5%, and 3% body weight for the first, second, and third month, respectively. After 90 days, the Highest growth performances (determined in terms of average weight) were recorded in T1 (27.5±2.5 g) and T2 (22.4±2.8 g) while T3 (18.2±3.5g) recorded the smallest growth. Production differed significantly among treatments (P<0.05). Feed conversion ratio (FCR) of 1.0, 1.02 and 1.05 in T1, T2 and T3, respectively were not significantly different (P>0.05). Survival was significantly different among treatments (P<0.01). Highest survival (100%) was attained in T1 with lower stocking density, followed by T2 (96%) and T3 (90%). Survival was greatly influenced by the stocking densities in all treatments. The water quality parameters and their monthly fluctuations recorded throughout the study period were found within the suitable ranges for the fish culture such as temperature 27.0 to 28.7 °C, dissolved oxygen 5.7 to 6.2 mg/lit, pH 7.2 to 7.5, Ammonia from 0.45 to 0.51mg/L, Hardness 105 to 110 ppm and Nitrite 0.152 to 0.161 mg/.