The objective of this study is to determine the impact of feeding tempeh dregs at varying doses on tilapia growth and survival (Oreochromis niloticus). The study was conducted from March to May 2023 in Wataliku Village, Kabangka District, Muna Regency. The study employed a completely randomized design with four treatments that involved the administration of tempeh dregs in the diet. These were designated as follows: treatment A (control) was commercial feed; treatment B was 10% tempeh dregs; treatment C was 15% tempeh dregs; and treatment D was 20% tempeh dregs. Each treatment was replicated three times. The data were subjected to analysis of variance (ANOVA) at a confidence level of 95% (α0.05). The study results demonstrated that the highest specific growth was observed with the addition of 20% tempe dregs, with an average of 2.97% per day. This was followed by 15% tempe dregs (2.47% per day), 10% tempe dregs (2.28% per day), and commercial feed (2.00% per day). The highest absolute growth was observed in the treatment that included 20% tempe dregs, with an average of 1.04 g per individual. This was followed by the treatment that included 15% tempe dregs (0.87 g per individual), the treatment that included 10% tempe dregs (0.80 g per individual), and the treatment that included commercial feed (0.00 g per individual). It should be noted that survival was 100% in all treatments. Analysis of variance (α0.05) demonstrated that administration of tempe dregs at varying doses had a statistically significant impact on the specific and absolute growth of tilapia larvae (Oreochromis niloticus).

Delays in hatching of fish eggs are influenced by several factors such as water quality instability during rearing, including; temperature, DO, pH. Papaya leaf is one of the plants that can be used to accelerate the hatchability of fish eggs. Papaya itself can be used as a component to boost the immune system because it contains the enzyme papain. The purpose of this study was to compare the hatchability of nile tilapia (Oreochromis niloticus) eggs in the treatment of papaya leaf extract (Carica papaya) with different doses. This research was conducted at the Punten Cultivation Fisheries Installation, Batu City in December 2022. Using a Completely Randomized Design (CRD) where there were 4 treatments, namely: A) papaya leaf extract 4 mL/L, B) papaya leaf extract 6 mL/L, C ) papaya leaf extract 10 mL/L, and D) control without treatment. In each treatment there were 3 repetitions. The ANOVA test was used to compare the effect of papaya leaf extract on hatchability of tilapia eggs, and was followed up with the BNT test if there were significant differences in the treatments. The results showed that there were significant differences in the treatment with the addition of papaya leaf extract on the hatchability of tilapia eggs, with 4 mL/L treatment) being the best treatment in increasing the hatchability percentage of tilapia eggs by 88.33%. There is a tendency that the higher the papaya leaf extract, the egg hatchability decreases.

Phytoplankton is a bio-indicator of fertility in waters. This study aims to determine the impact of detergent and pesticide waste on the phytoplankton community structure in in tilapia aquaculture media. The phytoplankton identification stage was carried out at the MIPA Laboratory Almuslim University. The parameters studied were phytoplankton abundance, diversity index, uniformity index, dominance index, and water quality parameters. The results of this study showed that detergent and pesticide waste at the end of the study had caused a decrease in the abundance value of phytoplankton by 3,250 individual/L and 3,750 individual/L. In the control treatment, the highest phytoplankton composition was dominated by Chaetoceros sp., while the pesticide and detergent treatments were dominated by Golenkenia sp. and Microcystis sp. Exposure to detergent and pesticide waste reduced the diversity index value, the phytoplankton uniformity index value. At the beginning of the study, it has a moderate diversity index (H '= 2.485–3.072), while at the end of the study it shows low diversity (H' = 2.111–2.375). Furthermore, at the beginning and at the end of the study there was a decrease in the uniformity index value (E = 0.87–1.01) and (H '= 0.88–0.94).

One of the common diseases found in tilapia is a streptococcal disease caused by the Streptococcus agalactiae bacteria. Treatment of this disease is generally done by using antibiotics.  The use of antibiotics in controlling disease in fish can create resistant bacterial strains with certain doses. The use of vaccines is one of the alternative control methods in fish defence against infections. The purpose of this study was to analyze the efficacy of vaccination on seeds through immersion using attenuated active bacteria to increase immunity at the beginning of the spread of streptococcosis disease. The vaccine used was obtained from attenuated Streptococcus agalactiae bacteria through repeated passage ten times. Vaccination was carried out through oral vaccine. Challenge tests were carried out on days 7, 14, and 21 days after vaccination on tilapia larvae by immersion. The result indicated that vaccination using attenuated bacteria could increase lysozyme activity at each observation time compared to control. The mortality of post-challenged larvae on days 7, 14 and 21 post-vaccination was lower than that of unvaccinated seed. The percentage of RPS values up to the 14th day of observation has increased and tends to decrease on the 21st day.