I am missing as much as 7 polyps a day. Some days not noticing anything, other days missing a small patch. Seems to be the same 2-3 colonies. Not for sure when they are all gone if whatever is eating them will move on. I have a power brown tang, hippo tang, and a pink tail trigger. I thought it might be the hippo, but I took him out and placed him in quarantine for 3-4 days. More polyps went missing while he was out. I have been checking out tank at night but no suspects. Does anyone have an idea who might be dining on my palys.