Eco One is an enzyme system that works as a bacteriacide. There is a similar system, The Natural, that is sold and explained at rhtubs.com. There are users of these systems that swear by them. They tend to be very easy on the skin. They should be used with a low dose of chlorine, though many don't but this would be risky, IMO, because these are not sanitizers. Like ozone, silver, copper, etc., they do help but tend to be expensive and are not magic cures that eliminate the need for a registered sanitizer.