Gussy, are you sure you mean to say murex? They are carnivores. Here is a photo I took of a murex snail sucking the life out of a coral in my tank. I of course removed the vampire immediately after snapping the pic.
I've tried...it seems nobody can do it as there is no market for it. Seems that I'm the old weird guy who wants one. I was tempted to grab one during diving in Baja a few weeks ago, but didn't have the proper container and packing materials for it.