I have a idol that was being picked on by my powder blue for like a month after which I noticed the idol was getting thin but I'd always see him eat. I figured he wasn't getting enough food so I caught and put him in part of the sump that I use for holding fish and coral hoping that with no competition he'd be able to fatten up again but he still doesn't seem to be filling out. So for the last 4 days I've been given him medicated food for parasites. Does anyone have any thoughts or suggestions?