Similar to Chris' issue, I used as directed and lost a wrasse, rock beauty angel and orange diamond goby. Essentially anything that picked at the sand or hid/fed from the sand died. My lfs used it as well and lost the livestock in several of his tanks, again, fish that feed or hide in the sand. I don't know if I got a bad batch, or just got lucky when I used it before, but I will never use it again. I used UltraLife Red Slime stain remover last time as directed and had zero losses. Didn't have to shut off the skimmer either.

