Culture performance and financial business of leopard coral (Plectropomus leopardus), humpback (Cromileptes altivelis), and brown-marbled (Epinephelus fuscoguttatus) grouper nursery

The nursery phase is critical in grouper aquaculture, influencing survival rates, growth performance, and economic feasibility. This study evaluates the culture performance and financial viability of three economically valuable grouper species: Leopard coral grouper ( Plectropomus leopardus ), humpback grouper ( Cromileptes altivelis ), and brown-marbled grouper ( Epinephelus fuscoguttatus ) over a 90-day nursery period. Results showed that brown-marbled grouper exhibited the highest survival rate (82.5 %) and growth performance, achieving the most significant final length (12.32 cm) and body weight (14.02 g). However, it also had the highest feed conversion ratio (FCR = 2.81), indicating lower feed efficiency. Leopard coral grouper demonstrated a balanced growth rate with the lowest FCR (2.00), making it the most cost-effective feed utilization. Financial analysis revealed that leopard coral grouper had the highest profitability, with the most significant net present value (NPV = US$ 65,067) and internal rate of return (IRR = 91.70 %), along with the shortest payback period (1.45 years). Sensitivity analysis indicated that feed costs and market price fluctuations significantly influenced financial viability. The research's findings show that leopard coral grouper is the most profitable species for nursery production, having the highest income, profit, net present value, and IRR. However, brown-marbled grouper has the lowest production cost per unit, making it a feasible option for budget-conscious farmers. While brown-marbled grouper grew the fastest in terms of length and weight, leopard coral grouper maintained competitive growth performance while also having the highest market value, making it the most economically advantageous option. To improve grouper farming's financial resilience, future initiatives should maximize feed efficiency, minimize mortality rates, and employ sustainable aquaculture practices. • The nursery stage is vital in grouper farming as it influences survival, growth, and profitability. • Understanding the biological and economic is key to developing cost-effective nursery systems that boost production. • Despite the brown-marbled grouper’s faster growth, the leopard coral grouper offered better economic returns due to strong growth and higher market value. • Future efforts should focus on improving feed efficiency, reducing mortality, and adopting sustainable aquaculture practices