Ok, here is the problem, fish that eat aiptasia generally only eat them to a stump, so they never actually get rid of them... they just shorten them. LOL so they look gone... but will come back slowly. Peppermints are another option... but from what I've seen only a handful of them will actually go for aiptasia. Now as far as i know, Berghia Nudibranchs are the only ones that actually remove them completely (from what I have seen) from the tank, sadly they only eat Aiptasia so they will die unless you have an almost unstopable amount of aiptasia, or only get a few Berghia to control rather then exterminate the aiptasia (which in my books is fine, they are only a problem when there is plauge numbers of them). That also said, I actaully culture Aiptasia in a tank for the purpose of feeding my Berghia (in their "storage" tank not my DT lol because they are kinda pretty in my books), as well as for a butterfly fish that my friend has that is a super picky eater.