The researchers studied how the amount of tiny particles in wastewater affects a special filtering system's ability to clean the water. They tested different concentrations of these particles and found that having between 3000 and 4000 milligrams per liter gave the best results. At this level, the system removed almost all of the pollutants, like dirt and chemicals, from the water. Operating at lower levels caused the system to not work as well, leaving behind more contaminants. This information can help improve how we clean and reuse water in a more efficient way.