Daphnia magna is the best natural feed for tilapia larvae because of the nutritional quality that is suitable with the needs of the fish. The fermentation process was carried out to increase the number of microorganisms, increase metabolism in feed, increase growth, and enrich the nutrition of tilapia larvae feed. The purpose of this study was to find an increase in production and nutritional quality of tilapia fed by fresh, frozen, and preserved Daphnia magna. This study was conducted by using completely randomized experimental design with 3 treatments and 3 replicates. Feeding using fresh, frozen, and preserved D. magna mass cultured using fermented culture media of chicken manure, quail manure, goat manure, expired bread and tofu waste fermented by probiotic bacteria then cultured for 28 days. Tilapia larvae used in this study had stocking density of 48 individuals/L. Feeding was done in the first week of 1,022 D. magna per liter of water and 1,467 of D. magna per liter of water in the second week. D. magna was given as much as 5 times a day, ad libitum and feeding were carried out for 14 days. Observed data included relative growth rates (RGRW and RGRL), feed utilization efficiency (FUE), protein efficiency ratio (PER), and survival rate (SR). The results showed that different types of feed gave an effect (P<0.05) on RGRL. The values for RGRW, RGRL, FUE, PER, and SR are 10.05, 11.62%/day, 14.24, 0.23, and 60.18%, respectively. Based on the results of this study, it was concluded that the best feeding treatment for tilapia larvae was fresh D. magna.
Keywords: Growth, Larvae, O. niloticus, Daphnia magna, Fermentation