I keep a pair of dragonface pipes in my 150 with a mystery, melanurus, yellow coris, green wrasse, springeri dottyback, pair of clowns, hippo tang, Midas Blenny, squareback anthias, dwarf moray, Chromis and a mandarin. Just like reef raff said, they're fearless and no one bothers them. They are very cool fish to watch, and do well in lots of flow.