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Mine gets the same white ring around the water line. My chemicals are perfectly in line and I recently did a full purge and drain. I bought some of those sponge things that are supposed to collect body oils and stuff. They look and feel like those mr eraser cleaner sponges sold for household use. I let it float around and every day or two I use it to wipe around the edges of my tub where the white film starts to build up. I have no idea what the stuff is but, left alone, it will get thick and sticky and hard to clean. When I did my purge, I used Ahhsome and used some baking soda and a rag to clean the edges. The Ahhsome didn't get all nasty like I've seen in the videos so either I had little biofilm in my new tub or I needed to run it through again. Regardless, it did not fix my issue with the white film.My spa guy told me to use less calcium next time I fill my tub. It is around 250ppm. I get zero foam in my tub but maybe too much calcium is collecting the body oils and stuff and it is settling against the water lines. No clue...but that sponge things does clean the white film very easily.
Mpkelley I doubt your tub had much time to get much biofilm. It was less then a month build time to when it was filled at your house plus I filled it at my store for you to try and we used a jet line cleaner when we drained it. There probably was very little to anything in those plumbing libes
I'm pretty much over trying to get the PH down. The procedure it calls for is to add 1 1/2 teaspoons and run the jets for 30 mins and test to see if the levels are down. I did this repeatedly for about 5 times and kept getting the same PH reading (8.0). It didn't really budge so I'm assuming that the aeration is counteracting the sodium bisulfate each time. With the taylor kit, as soon as I added one drop of the acid reagent I was in the 7.3 range, each time.It looks like that's where it will stay for now. I probably should start with a fresh batch of water and go from there.
pH lowering trick:Add whatever you are using to lower the pH (Muriatic Acid, Sodium Bisulfate) and DO NOT RUN THE JETS. Let the water stay calm. This will encourage the reducing agent to work more effectively. I do this all the time in our in ground pools and hot tubs here in the store. In fact, I know that it takes 4oz of sodium bisulfate to lower the pH from the tap when I am filling a new tub on the showroom floor. Thus- I toss the 4oz of dry powder into the footwell and by the time the tub is filled the pH is pretty spot-on. Try this and I bet you'll be fine. The only way it doesn't work is if you're testing your pH at, say, 8.6 and that is the highest your pH reader can read but in actuality your pH is, say, 11. That is why you're adding so much reducer.
Bisulfate will not cause damage to your jets, etc. But if you are that concerned, dilute in a buck of water and pour in, leaving jets off.But I promise that adding it will not damage anything. As Beck0101 noted- Sometimes you just have to slap it in the face. Keep track of what you end up adding in total and next time you fill your tub toss about that entire amount into the footwell. By the time the tub is filled, kicks on and runs a cycle you'll be where you need to be with your pH.