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I have a brownish spot on my floating bubble blanket, right above the ozonator.
I read that over /mis-use of dichlor is more apt to discolor and damage your cover than ozone.
I use dichlor, ozone and N2 cartridge. It works great. I haven't had tub long enough to experience any damage due to ozone. If it does help keep the nasties away, it is worth it IMO. After all that is the most important consideration. My dealer (sundance) said the ozonators are really only "necessary" if tub is left without daily maintenance for extended periods of time.
I've been researching the benefits of using ozone recently. I use it in my spa, but I didn't know why. So far, the best reason I've heard for using ozone is this: The ozone removes ammonia and nitrogen from the water. If left in the water, these would combine with dichlor to form chloramines. Without them, chloramines can not form. This means your chlorine remains in the tub longer as a sanitizer. So, I get to use less chlorine and I don't need to shock. Without adding as many chemicals, my TDS will stay lower. With low tds, I should be able to maximize the time between water changes. BTW, the ammonia and nitrogen are added to the water through sweat, urine, feces, saliva, etc., another words, soaking. I've read differing opinions about ozone being a sanitizer or oxidizer in water. I've seen it said that it's only an oxidizer. I've read that it is a powerful sanitizer in water and kills germs, viruses, and fungi. I'm a germaphobe, so I feel better knowing it's there, even if it ends up degrading my cover.
With my present routine, I add MPS weekly with dichlor after use and no ozone or N2. I never register any combined chlorine and my free chlorine levels are lasting longer than ever.
So Tony, you really are shocking with MPS each week, yes? That would be why there is no CC registering. Dichlor after each use and MPS once a week. You never use dichlor to shock?
I have had an ozonator in my jacuzzi since inception. I have NEVER had ANY pillow nor cover issues related to such ozone usage. The ONLY issues I have had are with my recent chemical balance issues. MPS and chlorine (and PH up and PH down and...) is what has now damaged my headrest (they are bubbling and peeling). So, it's not the ozone that has been at fault but rather it IS the chemical balance. Quit trying to pin things on Ozone as a deterioration facilitator. By the way, I've NEVER used MPS UNTIL my recent water balance issues so it's MUCH more likely that MPS is the solitary contributing factor to the damages those on here are stating. I am going on five years with my cover and it still shows NO signs of water saturation (maybe I have none because I never used MPS?). I am starting to see some deterioration on the OUTSIDE of the cover from sun and elements on the outside of the tub but nothing "tub-facing". I have periodically cleaned the tub-facing surface with a baking soda/water mixture and that also has not done any damage over the 4 years I've owned it and I do this probably about once every 3 or 4 months.