I thought of goniopora, too, when I read this thread. I bought one after lots of research and had it eating cyclopeeze, growing, and extending beautifully. I think it all depends on the level of specific care you're able to give a difficult specimen....as well as the idea that, if you're willing to give that care, you might save it from dying slowly in a tiny tank at some pet store!
In the end, my tomato clown--who had a voracious appetite for violently cuddling with my goniopora--forced me to get rid of it.
