Holothuria scabra is widely used in traditional medicine or consumed as a healthy or exotic food, causing wild stocks to decrease. Therefore, aquaculture is the best solution to address this issue and support the growing market demand. However, up to now, H. scabra production is facing problems related to the nursery phase, survival rate of larvae and juveniles, production cost, and broodstock for mass production. In this study, the juveniles of H. scabra were divided into three different stocking densities and fed with 1 g of dissolved Spirulina powder once on alternate days. Their length was recorded every two weeks. After six weeks, the juveniles reared with 100 individual densities showed the highest survival rate at 80% compared to 200 and 400 stocking densities. Meanwhile, every tank showed a positive growth rate, indicating that Spirulina powder could potentially promote the growth of juvenile H. scabra. The specific growth rate for stocking density at 100, 200, and 400 were 1.2, 0.86, and 1.37%/day, respectively. In conclusion, the optimum initial stocking density is between 100 and 200 individuals for a 1-ton fibreglass tank with a 500 L water capacity. The Spirulina can be used as the main protein source as compared to other diets for juvenile H. scabra.

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