COMMON USES FOR DISTILLED WATER, STEAM IRONS AQUARIUMS WATERING PLANTS CAR COOLING SYSTEMS LABORATORY EXPERIMENTS FACE WASH(acne treatment), HAIR WASH(as a hair fall treatment) Reverse osmosis filters the water through a special material called a semipermeable membrane. this material allows fluid to go through, but it removes salt and impurities. Distillation boils the water and then condenses the steam back into a liquid to remove impurities and minerals.