Effectiveness of the Combination of Alum (Al₂(SO₄)₃) and Calcium Hydroxide (Ca(OH)₂) Coagulants in the Removal of Manganese (Mn) Using the Coagulation-Flocculation Process: Efektivitas Kombinasi Koagulan Alum (Al2(SO4)3) dan Kalsium Hidroksida (Ca(OH)2) pada Penghilangan Logam Mangan (Mn) Menggunakan Proses Koagulasi-Flokulasi. Stannum [Internet]. 2024 Oct. 31 [cited 2025 Oct. 25];6(2):71-8. Available from: https://journal.ubb.ac.id/index.php/stannum/article/view/4301