In search for a potential fishmeal alternative, six-months feeding trial was conducted to examine the effects of replacing fishmeal (FM) with black soldier fly larvae meal (BSFLM) in the diets of black molly, Poecilia sphenops on growth performance, feed utilization, survival and whole-body composition. Five iso-nitrogenous diets (40%) were formulated containing 0%, 11.49%, 22.98%, 34.47% and 45.96% BSFLM, replacing 0%, 25%, 50%, 75% and 100% FM protein and named as D0, D25, D50, D75 and D100 respectively. Uniform sized (0.025±0.001gm) 30 black molly juveniles were randomly assigned to one of fifteen aquariums, having five dietary treatments with three replicates. At the end of feeding trial, significantly higher final weight (2.41±0.03gm), final length (4.75±0.03cm) and specific growth rate in percent (SGR%) (2.32±0.04) were found in the D50 diet fed set, followed by the D25 set and significantly lower final weight (0.91±0.08gm), length (3.43±0.03cm) and SGR% (1.97±0.04) were obtained from the D100 set. Food consumption was observed significantly higher in the D50 set (2.79±0.01gm) and a lower in the D100 set (2.65±0.05gm). The value of FCR was significantly higher in the D100 set (3.03±0.25), whereas the best value of was noted in the D50 set (1.29±0.01). Survival percentage was ranged from 88.89% to 98.89% and had no significant effect of dietary treatment. No effects of different dietary treatment on whole-body composition were observed. Overall, BSFLM could be incorporated in black molly diet up to a 75% FM replacement rate with no adverse effect and the optimum FM substitution level is 50% with 22.98gm/100 gm BSFLM.
