Hey out there! I found this website this morning looking for some advice on removing stains from my pool liner. I have a Doughboy oval above the ground pool .... 11,000 gallons. My pool water is clear. I don't cover my pool during the winter. We have several maple trees on the side so leaves, tree pollen, etc get in the pool. I keep leaves etc out of pool all winter. A couple of years ago we had a terrible time with pollen. So I believe the stains are organic but am not sure. How do I start ... Where do I start. Pool is about 5 yrs old. need help please.