Biological Evaluation of Brachionus rotundiformis and Nitzschia sp. as Initial Feed for Siganus guttatus Larvae

The availability of quality exogenous feed suitable for mouth opening is very decisive survival of the larvae ofSiganus guttatus. This study evaluates the application of two live feeds for survival, growth, and the choice of feeding index for S. guttatus larvae. Three treatments tested different types of natural feed, namely Brachionus rotundiformis with a density of 7-10 ind mL-1 , Nitzschia sp. with a density of 5 × 105 ind mL-1 , and a combination of these two live feeds. Life feed was given to S. guttatus larvae that were one day after hatching (D-1) with a total initial length (TL) of 2.429 mm and a density of 15 individuals L-1 . Larvae were reared for 15 days indoor system using a tank with a salinity of 24-25 ppt as much as 2300 L. The results showed that B.rotundiformis is a type of feed that produces a survival rate of 0.513 ± 0.05c%, the relative length growth was 32.107 ± 0.83c% which was significantly different (p <0.05) and had an IP value of 78.69%. The B. rotundiformis type feed is the preferred feed for S. guttatus larvae, supporting growth and survival.