Review on 🐠 Seachem Prime 500ml (3 Pack) - Ultimate Water Conditioner for Aquariums by Beverly Smith

I normally love Seachem Prime and have been using it for years but there is a black residue in the bottles I have received. I haven't done any water testing to see if it works, but it's still an issue and not worth risking the welfare of some fish. Too bad my return window closed before I realized these bottles are no good. If you buy it, open all your bottles before the return window closes. $$ in the wind.