Fuente: WIPO "tomato" The present invention discloses a modular treatment system and its operational method that enables recovering reuse-quality water from grey water discharged from individual houses and apartments. The present invention serves as a replacement for the existing soak pits where the grey water is disposed of without any treatment, leading to contamination of water environment. The invention integrates anaerobic and aerobic biofilms on natural fibre and various macrophytes to treat greywater effectively. It is particularly suitable for household and community-level applications, offering a sustainable solution to reduce freshwater consumption and mitigate water pollution.