One of my amanos seems to have pretty bad shell rot. It looks like a few parts of her exoskeleton has eroded and is almost outlined in brown. I've been trying salt baths for the last few days with seemingly no effect and I'm doing a 75% water change this weekend when I have time. I recently read that levamisole can help but I'm not exactly sure how to treat it. Could I do like levamisole baths in a separate container or should I just treat the whole tank?