II've been using Clearwater's ionization system since 2006 in my 20x40 vinyl pool. I find it to be far superior to chlorine economically and functionally. Anyone with questions can ask away. I would never switch back. The only downside is you have to learn about it yourself. I haven't found a pool store around Long Island that knows anything about them. Not a real big problem though because they are easy to maintain and operate.