Have staining on the bottom perimeter of my gunite pool where I pour my liquid chlorine. It occured in July shortly after
when within two weeks our pool was inadvertently treated twice with our normal dosage of copper based algacide.

The staining is in a narrow band exactly where I pour my liquid chlorine. I'm told that liquid chlorine reacts with excess copper to create these type of stains.

I've eliminated organic, chlorine triclor has no effect. . Have tried Jack's Stain ID kit but staining is in the deep end and it's hard to get enough product on the staining.

So, I'm wondering if anyone can recommend a copper stain removal product. There are so many brands i.e  Jack's, Natural Chemistry etc., I'm not sure which to try first.

We are in Florida so I hope to attempt this sometime  in January.