Enhancing Survival Rates of Cirrhitichthys falco Larvae Through the Inorganic Fertilization Method

Aquaculture techniques for marine ornamental fish have advanced rapidly but remain in their early stages, with challenges in providing suitable food for larvae. This study investigated using inorganic fertilization to raise Cirrhitichthys falco larvae. The fertilized group (F group) received inorganic nitrogen and phosphorus (N: 700 µg L⁻¹, P: 100 µg L⁻¹) without supplemental feeding, while the control group (C group) was fed the ciliate Euplotes sp. without fertilization. Key measurements included nutrients, water conditions, chlorophyl a, zooplankton density and diversity, and larval survival. Results showed higher phosphorus, nitrogen, dissolved oxygen (DO), pH, chlorophyl a, and zooplankton density in the F group (p  < 0.05), with zooplankton mainly composed of Strombidium spp. The F group also had significantly higher larval survival rates and growth compared to the C group (p  < 0.05). This suggests that inorganic fertilization stimulates natural prey production, enhancing survival and growth, and reducing the need for specific feeding strategies in marine fish larviculture.