I've used Aptasia - X, they disappear for a while but come back again. I tried some Peppermint but they didn't last with my Wrasse around. I added a Copper Band Butterfly not for the sole reason of eating the Aptasia I just loved the fish. He ate them at first but now that he's well fed he doesn't touch them anymore and they are starting to spread. My last resort is getting some Berghia Nudibranch, all they eat is Aptasia nothing else. I was reluctant in the past because they are expensive and worried about the Wrasse eating them. After a little research I found that they are nocturnal so crossing paths with the Wrasse is unlikely because he's in the sand an hour before the lights go out and from what I've heard is they taste lousy to the fish. I plan on placing an order in the coming weeks when the temp warms up bit and don't have to worry about cold temperatures and delivery.
