I need help!!! Newbie with stains. I did the vitamin c test and had a clean spot so I ordered ascorbic acid, took the chlorine down to zero, treated with 10 lbs of ascorbic acid (I went slowly at first, no change so kept adding more). PH is now 7.2, total alkalinity 180 water is cloudy and the stains look worse. The pool is 35000 gallons, I do fill with well water and I use a nature 2 cartridge. The pool was replastered about 4 years ago and the stains are a couple of years old, they were not real bad. (they are now) If the stains are not metal...what are they?