siti nuratiqah khairul and S. Ahmad, “Transforming Silica Water Filter Waste into Sustainable Fertiliser”, rpmme, vol. 6, no. 2, pp. 10–17, Dec. 2025, Accessed: Apr. 07, 2026. [Online]. Available: https://penerbit.uthm.edu.my/periodicals/index.php/rpmme/article/view/21429