Effects of Biofloc on Water Quality and Growth Performance of the Nile Tilapia (Oreochromis niloticus) in a Zero-Water Exchange System

The use of biofloc technology (BFT) can enhance aquaculture productivity, which promotes the attainment of sustainable development goals. With the help of this technology, production might increase while reducing environmental effects. The current study was administered to determine the impact of efficient microorganisms, carbohydrate sources such as molasses and starch, and their mixture in a biofloc (BFt) system on water quality and the growth performance of the Nile tilapia (Oreochromis niloticus). A 45-day experiment employing two carbon sources, molas and starch, was carried out to examine the effects of various biofloc systems. A total of 180 healthy Nile tilapia (Oreochromis niloticus), with an average body weight of 5.3 ± 0.6g were stocked in each [A1] tank (15 fish/ replicate). Four experimental treatments were designed as follows: T1: control; fish were fed a basal diet without any addition of carbohydrate source. T2: supplementary molas; T3 supplementary starch. T4: with supplementary the mixture from molas and starch. Fish were distributed randomly into twelve circular tanks. Measures of the biofloc conditions in the current investigation were temperature, DO, pH, conductivity and ammonia. Dissolved oxygen concentrations, pH, and ammonia were considerably greater in the biofloc groups compared to the control group; whereas, water temperature and conductivity were not statistically different between groups. Statistically significant (P≤ 0.05) differences in the final weight, weight gain, survival rate, SGR, condition factor and FCR were recorded in all treatments compared to the control. Finally, the findings suggested using a combination of useful microbes, molas, and starch as a carbohydrate source in fish water tanks for the optimum effects on tilapia culture raised under a zero water exchange system.