So I have a 30 gallon I had 4 goldfish and pleco. Tank got ich then the fish got severe fin rot. I have two goldfish and pleco left. I put the pleco In a 2.5 tank so I can massively treat the tank with salt and Melafix. So far the fish don't seem to be doing better. Anyways, if they all do end up passing away what should I go from the tank? Should I rinse the whole tank out or what? Basically all I'm asking is if the fish pass away what should I do with the I fected tank