A WI has a built in filter, which has pretty long life ( approx a year) . The water is passed through several layers, which removes bad stuff and then mineralizes the water.
Then water is ionized, by passing an electric current. Similar to "electrolysis of water". The alkaline and acidic waters are separated by a porous membrane. The Alkaline Water is consumed internally. This water is hydrogen rich and has antioxidant properties because of dissolved Hydrogen gas. It has negative ORP....