the reason i ask this question, is because last year, we had a pool store experience (and ended up with quite a bit of copper stains) got that cleared up, but this year, the stains are coming back. (so maybe we didn't get it cleared up like we thought we did!) i did the metal stain protocol, and cleared the stains, but now they're coming back again. we use bleach, borax, the very occasional triclor puck (only 2 so far this year). i've got polyquat, and metal out, and use them sparingly. I'm of the understanding that none of the above contain copper. And yet the stains have returned. I'm all set to go with another stain removal session, but I'm wondering if i'm missing something else.
to that end, I checked our town's water quality report, and it says
0.19 ppm at the 90th percentile
I don't know anything about this, so I have no idea if that's high or low, if i'm not using the sequesterant/metal out on enough of a regular basis to prevent the stains (every other week), or if I'm inadvertently adding it somehow.
My #'s are as follows: