In the context of healthy and sustainable alternatives to fishmeal, insect meal asserts itself as a potentially healthy ingredient in aquafeeds. The aim of this study was to determine the possibility of successfully replacing fishmeal with Hermetia illucens larvae meal in the diet of the hetero-clarias hybrid, and to improve the overall bioavailability of the meal by supplementation with an enzyme complex (Hostazyme X). There were eight treatments: 0, 40, 50, and 60% replacement of fishmeal with larvae meal in the diet, with and without the enzyme supplement. In total, 240 fish with a mean weight of 11.43 ± 0.32 g were employed in the treatments for 80 days. Growth parameters (specific growth rate, feed conversion ratio, daily feed intake, daily weight gain, percentage weight gain, survival rate, production index, metabolic grow rate), hematological parameters and blood serum biochemistry were determined and analyzed. There was an improvement (p < 0.05) in most growth parameters for fish fed experimental diets. Blood parameters, although significantly different (p < 0.05) in some cases, were within a normal range for fish physiology. Thus, the partial replacement (40%) of fishmeal with larvae meal and supplementation with an enzyme complex produced the best growth performance compared to other treatments and controls.