Jakarta is removing thousands of invasive pleco fish from its rivers in an effort to restore damaged ecosystems. Known locally as “janitor fish” or “sweeper fish,” plecos have spread rapidly through waterways such as the Ciliwung River, where activists and fishermen say they are displacing native species and contributing to riverbank erosion. City authorities have already removed around 12 tons of plecos, but experts warn that eliminating the fish alone will not solve the problem. Pollution from untreated sewage, plastic and waste continues to degrade river health, while studies indicate plecos in the Ciliwung contain high levels of heavy metals and harmful bacteria. The campaign has sparked a wider debate about invasive species, water pollution and the urgent need for better wastewater management in Indonesia’s capital.