I had an aiptasia problem to, but I got some pepermint shrimp to get rid of them. Fresh water don't work. I don't know who ever cam up with that idea, but i tried it and they multiplied like crazy after i shot water in them. They seem to throw up all their babies when you try to murder them.lol the best way to get rid of them is with shrimp or I think a copper band butterfly eats them too.