Biocides for Reverse Osmosis are chemical agents used to control and eliminate microbial growth such as bacteria, algae, and fungi in RO systems. These microorganisms can form biofilms on membrane surfaces, leading to fouling, reduced permeability, and decreased system efficiency. The biocide works by disrupting the cell structure of microorganisms and preventing their growth and reproduction. This helps maintain clean membrane surfaces and ensures stable water flow and consistent filtration performance. In reverse osmosis systems, biocides are used both as pretreatment chemicals and for periodic cleaning to prevent biofouling. Proper use of biocides helps maintain high salt rejection efficiency and reduces pressure drop across membranes. By controlling microbial contamination, biocides play a critical role in extending membrane life, reducing maintenance frequency, and ensuring reliable operation of RO plants in industrial, municipal, and desalination applications.