The objective of the present study was to evaluate the giving of baker yeast and taurine mixture in culture media on the population density of Daphnia sp.. The completely randomized design method was used in this study with four treatments and four replications. The treatments studied were the giving of chicken manure 1 g/l as control (P0), the giving of baker yeast and taurine mixture 1 g/l (P1), the giving of baker yeast and taurine mixture 2,5 g/l (P2), and the giving of baker yeast and taurine mixture 4 g/l (P3). Daphnia sp. stocking density was 100 individu/l with the size of  1,5-2 mm. The culture period of Daphnia sp. culture was 16 days. The parameters observed in this study are population density, peak population, and water quality parameters. The ANOVA test showed that the giving of yeast and taurine mix in culture media gave significant effect on the population density of Daphnia sp. Population density of  Daphnia sp. the highest was obtained in the treatment of giving 2.5 g / l of baker yeast and taurine mix in cultural media (P2) which is 1320,35 Ind / l with a peak population on the 10th day.

The objectives of the present study were to evaluate the best combination of biofloc density in culture media and percentage crude protein content on feed on growth performance, survival rate and feed utilization of the black tiger shrimp (Penaeus monodon) culture system. The Completely Factorial Random Design (CFRD) was used in this study. The first tested factor is the percentage of crude protein in the diet at three levels namely; 35%, 30%, 25%, and the second factor is biofloc density at in three levels namely; 5mlL−1, 10mlL−1, 15 ml L−1. The results showed that the combination of 35% crude protein combined with 10mlL−1 biofloc gave the best results for all measured parameters, with a survival rate of 100%, absolute growth rate was 17.207g, daily growth rate was 0.58g day−1, specific growth rate was 3.528% day−1, feed conversion ratio (FCR) was 0.974, and the feed efficiency was 102.7%. It is concluded that the best combination of crude protein and biofloc density that 10 ml L−1 floc and 35% crude protein diet.

This study aimed to examine the effect of Gamal leaves flour supplementation in commercial feed on the growth of Nirwana tilapia (Oreochromis niloticus) fingerlings. The experimental design used was a non-factorial completely randomized design consisting of four treatments and four replications. The treatments studied included commercial feed without supplementation of Gamal leaves flour as a control (P0), commercial feed with supplementation of Gamal leaves flour 10% kg−1 feed (P1), commercial feed with supplementation of Gamal leaves flour 15% kg−1 feed (P2), and commercial feed with supplementation of Gamal leaves flour 20% kg−1 feed (P3). Nirwana tilapia fingerlings were stocked at a density of 1 fish L−1. Nirwana tilapia fingerlings size ranges from 2-3 cm. Nirwana tilapia fingerlings maintenance period lasts for 40 days. The Annova test showed that the treatment gave a significant effect on the weight gain, length gain, daily growth rate, and feed conversion ratio (P < 0,05), but did not give a significant effect on the survival rate of Nirwana tilapia fingerlings (P > 0,05). The best dose to increase the growth of Nirwana tilapia fingerlings was commercial feed with supplementation of Gamal leaves flour 10% kg−1 feed.

Biofloc technology (BFT) is an alternative that can be used to provide additional feed source in addition to control and improve water quality for aquaculture. BFT can be done by adding an organic carbon source to increase the C/N ratio in  the culture media to stimulate the growth of heterotrophic bacteria. The results of the observation were that the highest specific growth rate was obtained in treatment B (5ml floc) with an average value of 2.80 grams/day. The highest average length value in treatment B (5ml floc) reached 10.26 cm. The highest survival rate was in treatment B (5ml floc) with an average value of 86.78%. The highest efficiency value was found in treatment B (5ml floc) with an average of 95.90%. Based on Duncan's further test (p<0.05) the application of biofloc with an external carbon source from sweet sorghum had a significant effect on the specific growth rate, absolute growth, survival rate and feed efficiency of tilapia fry. Keywords : Biofloc; Sweet Sorghum; Tilapia Nirwana ; Aquacukture