Evaluating optimal stocking density for the tank polyculture system of whiteleg shrimp (Litopenaeus vannamei) and all-male giant freshwater prawn (Macrobrachium rosenbergii) postlarvae

Whiteleg shrimp (Litopenaeus vannamei) and giant freshwater prawns (Macrobrachium rosenbergii) are significant crustaceans in aquaculture, and they are compatible for bi-farming systems. This study assessed the best stocking density for a tank-based polyculture system comprising postlarval whiteleg shrimp and all-male giant freshwater prawns. The study used a completely randomized design with three replications. Whiteleg shrimp were stocked at four densities (5, 10, 15, and 20 individuals/m³—ind m?³), whereas all-male giant freshwater prawns were maintained at 5 ind m?³ in 4 m³ tanks with partial shading. After two months of rearing using a commercial pellet feed (42% crude protein), survival rates, as well as weight and length growth performance parameters (final mean weight, daily weight gain, specific growth rate in weight, final mean length, daily length gain, and specific growth rate in length) of both trial animals, were significantly higher at shrimp stocking densities of 5 and 10 ind m?³ than 15 and 20 ind m?³ (P?0.05). There were no significant changes in survival rates or growth performance parameters between densities of 5 and 10 ind m?³ (P?0.05). Productivity was significantly lower at 5 ind m?³ compared to other densities (P?0.05), while there were no significant differences among higher stocking densities (10-20 ind m?³) (P?0.05). The findings indicate that a stocking density of 10 ind m?³ for whiteleg shrimp and 5 ind m?³ for all-male giant freshwater prawn offers the optimal balance of growth, survival, and productivity in the experimental system.