Effect of inorganic fertilization on survival of Pomacanthus semicirculatus, Paracanthurus hepatus and Cirrhitichthys falco larvae

• Main Authors: Tsung-Jui Lee, 李宗叡
• Other Authors: Ming-Yih Leu
• Format: Others
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/64589544610921106876

碩士 === 國立東華大學 === 海洋生物研究所 === 103 === In recent years, aquaculture technique in marine ornamental fish has been developed rapidly yet only in its infancy. There are some bottlenecks in marine ornamental fish larviculture, one of which is to provide initial food for fish larvae. In this study, we used an inorganic fertilization method to raise Pomacanthus semicirculatus, Paracanthurus hepatus and Cirrhitichthys falco at the National Museum of Marine Biology Aquarium (NMMBA). Fertilization group (F group) was maintained by adding inorganic nitrogen and phosphorus (N:700 µg/L, P:100 µg/L), whereas Control group (C group) was fed with Euplotes sp. without any fertilization. We measured nutrients, chlorophyll a, physico-chemical parameters, as well as zooplankton density and diversity, and larval survival during the experimental period. The results showed that the concentration of phosphorus and nitrogen in F group were significantly higher than in C group (p<0.05). The NH3-N between two groups were not significantly different (p>0.05), and the concentration in both groups were lower than 50 μg/L. Dissolved oxygen and pH in F group were significantly higher than in C group (p<0.05). Chlorophyll a and zooplankton density were significantly higher in F group than in C group (p<0.05). The zooplankton in F group composed primary Protoperidinium spp. and Strombidium spp. The larval survival of Pomacanthus semicirculatus and Cirrhitichthys falco in F were significant higher than in C group (p<0.05), and the length of Cirrhitichthys falco larvae in F group was significantly higher than in C group (p<0.05). We conclude that the inorganic fertilization method provides high concentrations of chlorophyll a, high zooplankton density and diversity, and subsequently increases larval survival.