help! stains

[Poolsean]

hmmmm.... gray stains are usually plaster issues, called mottling. Although this appears randomly in more than one spot in your pool. But coincidentally, the diamond brite is rough in that same area tells me that it is a plaster issue rather than a metallic or organic stain.

[xoroniox]

hm thanks for your responce, i think are you correct. however i dont remember seeing the stain 6months ago or maybe i just never noticed it, it is pretty small in either case i guess there is nothing i can do assuming it is a plaster related issue correct? besides replaster.

[Poolsean]

Don't quote me on this, but lowering the pH level may whiten it, similar to acid washing the surface.
Short of draining and acid washing the surface, there are "no drain acid wash kits".
You can also try to isolate the area and dose some acid over the area.

Since you're in South Florida, so is SGM (they're in Pompano). May be worth a call to them to see how they recommend treating it.