The use of subtilis in the improvement of water might provide significant economic benefits. Bacillus subtilis, Bacillus pumilus, and Bacillus licheniformis may all improve water quality when exposed to it. Recent research examined the effectiveness of four bacterial isolates: Bacillus subtilis, Bacillus pumilus, Pseudomonas pseudoalcaligenes, and Brevibacterium halotolerant. When applied to water, probiotics improve the quality of the water supply by decreasing harmful ammonia levels and raising nitrite and nitrate levels. Additionally, it inhibits the development of several pathogenic microorganisms in water. Water microorganisms' diversity might be affected by bacterial complexes. B. subtilis was found to have the highest total metal content of all of the isolated bacteria. Variations in immobilising activity were shown to be very sensitive to water temperature, humidity, and pH. Prior to treatment, the effluent was analysed for Biochemical Oxygen Demand (BOD), Dissolved Solids (DS), Colour, Intensity, and Heavy Metals. After determining which Bacillus subtilis strains had the greatest potential for degradation, those bacteria were transferred to an air-sparged bioreactor. In this investigation, we used bacterial isolates that can survive in the presence of metals, including Pseudomonas aeruginosa KP717554, Alcaligenes feacalis KP717561, and Bacillus subtilis KP717559. In order to determine the frequency of faecal coliforms (FC) and faecal streptococci (FS), membrane filtration techniques were used. Bacillus subtilis spores and MS2 phages were tested for their susceptibility to chlorine disinfection, and the role that water quality (pH, temperature, turbidity, and natural organic matter) played in the disinfection process was also investigated. Systems based on Biofloc Technology (BFT) improve water quality with the help of beneficial bacteria. Prior to treatment, dissolved organic matter, biochemical oxygen demand, nitrates, phosphates, and other metals were all reduced by at least 10%.