Pulled off my solar cover today after it being on for about five days. Found out boyfriend (who is very new to the pool thing) somehow thought he was being helpful and put several chlorine tablets in an old skimmer basket and set it on one of the white pool steps. Now the bottom two steps are very yellow and they look awful. How can I get the stains off? Don't think he would have done this but our automatic inline chlorinator broke and I'm just using liquid right now. Guess he didn't realize there was another way to add the chlorine and thought it would be kinda like a floating chlorinator in place of the inline. Anyway, please tell me there is a way to remove the stains? Thanks in advance