Ok thanks for your help, its appreciated. I think you are correct though and they are 90% all organic stains from the algae battles, most got a bit lighter with the bleach and scrubbing, however the grey stain has been there for awhile i just never bothered messing with it because its pretty small however i have had really high bleach levels even with this stain and never noticed any other stains or that stain get larger. when i scrub it, no affect. also the diamondbrite in that particular stain/area is very rough, much rougher than in all other areas of the pool, im not sure if that makes any diffrence, i will await more direction and information. thanks again. in the mean time i will continue to bleach and scrub the green stains.
-Arron