Membrane fouling is a big issue in water filtration systems using microfiltration and ultrafiltration membranes. This study looked at how fouling develops and how it can be removed during backwashing and cleaning. They used small-scale filtration systems with coagulated water and found that both types of membranes removed dirt and metals well, but struggled with organic compounds. The bigger organic molecules were somewhat removed, but the smaller ones passed through easily. Backwashing didn't clean the membranes well, but a two-step cleaning process helped remove some foulants completely.