Abd Wahab, N.A. and Ahmad, M.L. 2025. A Study on The Effective Use of Microorganisms using Different Amounts of Mudball and Wastewater Retention Time. ASEANA Science and Education Journal. 5, 1 (Apr. 2025), 1-8. DOI:https://doi.org/10.53797/aseana.v5i1.1.2025.