Interaction of salinity and natural feed on growth and survival rate of the Banggai cardinalfish (Pterapogon kauderni) for ex-situ conservation development

The Banggai cardinalfish (Pterapogon kauderni) is an endemic and protected fish. However, its exploitative use and damage to its microhabitat ecosystem have led the fish to be endangered. This study aims at determining the effect of salinity and type of natural food on the growth and survival rate of Banggai cardinalfish. The method employed is experiment with a factorial completely randomized design (CRD) encompassing salinity factor (26 ppt, 20 ppt, 14 ppt, and 8 ppt) and food factor (rebon shrimp, Artemia sp. and mosquito larvae). This study uses 36 aquariums as containers with a volume of 10 liters equipped with a Recirculation Aquaculture System (RAS). The animals used in this study are 360 Banggai cardinalfish with an average length of 28.31 mm and an average weight of 0.29 g. The stocking density is 1 fish/L with a rearing period of 30 days. The observed data include growth and survival rate, in which the data are analyzed by applying analysis of variance (ANOVA). The result of the analysis reveals that the difference in salinity level does not significantly affect the length and weight gain (F_count > F_table(0.05)), yet it affects the survival rate significantly (F_count > F_table(0.05)). In addition, the different types of natural food significantly affect the length and weight gain, and survival rate (F_count > F_table(0.01)).