I had a oak tree land in my pool during Sandy. We had to wait for claim agent to come and assess the damage. Pool was closed w/o removing all the debris because they wanted it drained to inspect. We opened up couple weeks ago, drained, power wash, filled so wouldn't damage pool while waiting for addtl claim response. Now some stains have come off but many still remain. They will cover acid wash but I think plaster damaged from 50' oak tree canopy and the staining needs plaster redone?