I've had this problem since opening pool for season in late May, and just now found this forum. Two local pool stores have not corrected my problem. My steps and ladder were covered with yellowish stain, sides and bottom spotty. I cleaned steps and ladder with united chem pool stain treat (oxalic acid, 5 lbs) and it worked. Didn't have time to do the rest of pool so hired pool company to "clean my pool". They dumped 6 lbs of oxalic acid and left me a bigger mess. I had a heavy white residue in the bottom of my pool which took me forever to filter out. I still had the original stains on the liner and they were beginning to come back on my steps. I used another 5 lbs of oxalic acid to work on the stains believing that was the remedy.
Needless to say I have poured the chlorine (trichlor and calcium hypochlorite) and shock, baking soda, calcium, algaecide, superblue, just to try to get my pool in balance, but it never was, and I still have stains. That's when I decided to look on the web for some answers. Last Friday I added 18 lbs of baking soda, and today (Tues) my TA = 28. My other readings are FC = 0.02, TC=0.36 CC=0.34. I quit adding chlorine last Friday when I started reading BBB. pH=7.5. CH=201. CYA=112
I had the pool place run the tests today. They also tested Cu=0.2, Fe=0.1, and Phosphates = 1000. I have added much algaecide?? I don't know what to do. Help, please!?