I wouldn’t use peroxideI'm not sure exactly what it's leaching, but the turf algea is impossible to remove and none of my CUC is putting a dent in it. From what I read only Urchin's go for this stuff, and my 3 don't seem to be doing much. I've heard this rock is bad news. Also the previous owner of this setup cycled the rock so there's no telling how much the rock has taken in. I think it is either hydrogen peroxide or this, and at this point I'd rather not kill off my entire biom with hydrogen peroxide.
It’s easy to overdose and kill stuff in your tank
Ask me how I know