I've heard a lot of stories where Angelfish like Emperors, Regal, Majestic will eat their LPS and softies but not eat SPS. I really love butterflyfish and know pyramids and zosters, longnose, certain henniochus and copperbands have a decent chance of not eating SPS. But my favorite butterflyfish are of the genus Chaetodon. Similar to the more SPS safe angelfish that aren't safe with other coral are there any Chaetodon butterflyfish that fit this description or will pretty much the entire genus happily munch on SPS as well?