
Moved into a house in February with a pool. We had an inspection but know no history of the pool itself except it’s fairly older (some asbestos on the deck). Since February, I’ve been bringing in pool samples every week and cleaning and balancing the water myself (it’s pretty fun).
A few weeks ago I noticed these spots. I was told to do two tests:
1. Rub the stains with a chlorine tablet. If the stains are removed, then it’s algae. This didn’t work.
2. Rub the stains with a vitamin C tablet. If the stains are removed, then it’s a mineral stain. This didn’t work either.
I was then told to try with a hard brush and elbow grease to remove the stains—and we tried our hardest and it didn’t work. The only solution that we tested was with a power hose but that took the plaster off of a test area. Whoops!
So I took my handy GoPro and took some shots. I was then told these are copper stains caused by possibly copper pipes, possibly older plaster, possibly having a higher pH (at times getting to 8.0 but I mitigated quickly), and possibly because I’ve been filling our water with a hose.
So a few questions:
1. What do you think this stain is? Pic attached with hand for size reference. If the vitamin C tablet didn’t remove the stain, then what could it be??
2. If it is copper, are there any other reasons why I’d have copper aside from what’s listed above?
3. How do you remove copper? I was told to use No Metal or Leslie’s Scale and Stain Remover, add a culator (I already have a larger one in since March but they should be good for 6 months and it’s only been 4). By the way, does an auto filler help with not adding copper to the pool?
Thanks in advance!