I was looking for a little help identifying a few stains.
I have my pool drained as I needed to bring my CH down and it was off the charts! I thought I would do an acid wash on it and refill but as I started the acid wash it wasn't helping. I think the brown is calcium buildup and the green may be copper? Then the black one I don't know but a pool guy suggested it was rebar staining through where the shotcrete was not deep enough.
Any help is much appreciated!