Hi - I have a 15,000 gal free form pool with a white pearl pebble tec finish. We have only had water in the pool for about 2 weeks. We live in a suburb of San Antonio and our huge live oak trees are dropping their pollen like mad. What concerns me is that they seem to be staining the finish. Initially the acidic water and brushing seemed to take care of the problem but now it looks awful. My husband is freaking out. Any suggestions?