Okay, so I'd like for this question to go answered without me being lectured, because I know I was an idiot for letting this happen. My dank is disgusting and it really could use a DEEP cleaning. I have a snail so the walls are algae-free, but the rocks and decorations are absolutely disgusting. There's waste in all the rocks and the decorations went from white to green. I think I need to get both the snail and the fish out for this cleaning. Is that bad? Will the fish be harmed? Will it hurt the tank in any way?