Effective microorganisms (EM) were used as a probiotic to help Nile tilapia fish grow better and stay healthy when exposed to copper pollution. The fish were given a small amount of copper for 12 weeks, and those not treated with EM showed damage in their gills, liver, and kidneys. However, the fish treated with EM had improved growth and better overall health, with less metal buildup in their bodies. This study suggests that using EM in fish farms can boost fish productivity and protect them from harmful pollutants.