I have a 170 gal. tub in my bedroom. It has an ozanator. I have been putting a quart of store bought 3% h202 in it once in awhile. Hope it doesen't corrode the pump. It seems to make the water more acid, so I need to find something to up the ph. mh puts h202 in his tub, and said he has never changed the water. It really feels good. I don't know either.