UV water purification treatment is a different process than a typical water filter uses, although they’re often used in conjunction with one another. A water filtration system attempts to remove and reduce the number of common contaminants found in tap water, which could include mercury, chlorine, copper, iron, hydrogen sulfide and more. A water purification system, such as this UV light technology, purifies water so that it’s up to 99.9 percent free of bacteria and viruses. Purifiers can also attack algae and fungi, inhibiting their development in your existing water system.