I have a large cedar that is dropping a ton of needles in my pool. No matter how often I run my skimmer/cleaner, they are still leaving stains all over my Pebble Fina finish. Does anyone have a product they'd recommend that will get rid of the stains with the least amount of damage possible to my finish? The only thing I know of is an acid bath, but that will slowly eat away the layer of finish I have (I think ), or ascorbic acid which, as I understand it, I have to apply directly to each stained area which is probably 50% of my pool and it could change the color of the finish in those areas. Any guidance would be appreciated!