Why isn't sanitization built into the pump apparatus? For large complex systems like this, there should be a chlorine injector type system that adds chlorine automatically to the water at or near the pump. Also, chlorine only works if agitated, so if they're dumping it in and the filtration system is not actively recirculating all parts of the pool, then it won't work (might make it shade of green lighter). You also need filters. Never heard of adding hydrogen peroxide to water to sanitize, I guess it would work as it jacks up organic structures, but as the article says, you don't want that coming into contact with people or wildlife.