Ok I have got an old tank that I resealed and am going to be setting up. It belonged to my mother and she has not used it for several years now. She still had the hood, filter and heater as well. However there appears to be hard water or lime deposit or something on them. Crusty white stuff. I tried just some vinegar water and that did not seem to do much for it. So I was wondering what I could do to clean everything up but not harm the fish that will be going into it. I wondered about using OxiClean as it would seem to be safe but figured that those on here would steer me in the correct direction. Thanks in advance.