I had one for several years in a mixed reef and it was well behaved but like the other said it is really hit and miss. Mine didn't touch my leathers, polyps, shrooms, or anemones but did eat a frag of LPS I tried. I didn't keep SPS so I dont know about that. I did keep mine very well fed in an old system with lots of natural feeding opportunities and multiple feedings and I think this is the key to successfully keeping an angel in a reef.