So, typical, I have a yeasty cup. This is my sort of luck, so I'm not surprised. I read about soaking it in apple cider vinegar, but what if I just covered it in gentian violet-or soaked it, I guess. (i'm unfamiliar with the consistency.) I know it would dye it purple...which is almost an incentive unto itself. ;) If it matters, I have a size 1 diva. Would it harm the cup to cover it in gentian violet?