After several failed attempts to clean my waterline with a pumice stone as well as acid, I found a succesful method using Bar Keepers Friend. This requires lowering your waterline a few inches. I used Bar Keepers Friend and water to make small batches of paste. I slathered the paste on about 3 feet of the tile, then pressed thin plastic into it. (I cut 3 or 4 inch wide strips of thin, clear plastic sheeting found in the paint supply department of a box store. You need something light and thin enough to stick to the paste like cling wrap). I applied this to my entire water line, which took a few hours, then I used a green scrub pad and water to scrub it, starting where I first applied it earlier in the day. I scrubbed it a decent amount, but honestly, I don't think I really needed to do much scrubbing at all. I think the acid in Bar Keepers friend had essentially dissoved the scale while it sat covered under the plastic. I used varying amounts of paste, it seemed to work no matter how much paste I applied, so I don't think it's necessary to apply it incredible thick. That might be creating more clean up and waste than needed. My tile was perfectly clean and shiny when I finished. I'm not even sure glass or soda blasting would have brought the shine back as well as this did. I just know it looks great. For maintaince, I'm trying a mixture of gysar tile soap and acid once a week. It takes about 5 minutes with a pole mounted scrub pad. I saw it on a Youtube video posted by a pool guy. He says it will prevent build up. Time will tell... If it works it's worth a few minutes a week.
As always, this may not work for every situation or tile. Make sure you test it on a small inconspicuous area of your tile before doing your whole waterline. I didn't build my pool. I think my tile is ceramic or porcelain, with a textured surface (typical pool tile), circa 2003.
I will note that I had to backwash my filter several times over the following days. I kept a bucket of water on the pool deck and tried to rinse my scrub pad in that bucket and not in the pool. I tried to keep as much Bar Keeper's Friend as possible out of the pool water. I bought this house a year ago and I'm sure the waterline had several years of build up that was being deposited into the water as I cleaned and rinsed the tile. I had also dissolved two large pumice stones trying to scrub this same scale off the day before. I could see the pumice residue on the bottom of the pool. I'm pretty sure the biggest offender for my filter was the pumice stone.
Unfortunately, I didn't take before and after pics. I honestly didn't expect it to work so well after trying so hard using other methods.
As always, this may not work for every situation or tile. Make sure you test it on a small inconspicuous area of your tile before doing your whole waterline. I didn't build my pool. I think my tile is ceramic or porcelain, with a textured surface (typical pool tile), circa 2003.
I will note that I had to backwash my filter several times over the following days. I kept a bucket of water on the pool deck and tried to rinse my scrub pad in that bucket and not in the pool. I tried to keep as much Bar Keeper's Friend as possible out of the pool water. I bought this house a year ago and I'm sure the waterline had several years of build up that was being deposited into the water as I cleaned and rinsed the tile. I had also dissolved two large pumice stones trying to scrub this same scale off the day before. I could see the pumice residue on the bottom of the pool. I'm pretty sure the biggest offender for my filter was the pumice stone.
Unfortunately, I didn't take before and after pics. I honestly didn't expect it to work so well after trying so hard using other methods.
