There are many misconceptions 'floating' around about pool and spa chemistry. One thing that we here quite often are the dreaded words: "I don't use any chemicals in my pool except chlorine." The thinking is that pools become 'overchemicalized' and what not. The truth is, the only 'Chemicals' that go into a pool are oxidizers, algeacides and Metal removers. pH adjusters are nothing more than salts that are present naturally in water. Calcium Hardness is nothing more than a mineral that gets added to many bottled waters. These additives make your water more healthy, not less.