I'm not sure which dragon fish you are talking about. I am aware of two with that common name. One of them is next to impossible to keep alive, the other is also called rock mover and gets to 2' long. It could be considered reef safe if you don't mind your reef being rearranged, rock dropped on your corals, etc. Thanks for checking first!
And if it is the rock mover one you're talking about, it's a dragon wrasse. Baby dragon wrasses have got to be one of the neatest fish I've ever seen - they're what got my interested in wrasses in the first place. But when they grow up, they are ugly and plain - black or grey I believe.
