I think I have been feeding a little too much and now I have some fuzzy gray/white stuff growing in my tank. I read in a few places that it could be a bacterial fungus. It only started growing in the last day - day and a half. My fish managed to fool me into thinking they would eat more than I thought. I had to remove decorations and clean them off as it was getting bad really quickly. Do I need to get a gravel vacuum, or do I just need to wait, or something else entirely?