Mix up some kalkwasser to a high concentration and use a siringe to squirt it rite in the middle of them and all over. Dont buy any fancy chemicals and you dont need to buy any livestock either. Try to keep your nutrient level down in your tank as well.
Kalkwasser is not harmfull in any way to your tank. Its a calcium suppliment that is added to tanks to help raise falling calcium levels and it also boosts ph. This will not harm anything in your tank accept for what you squirt it on in a high concentration or dosed improperly. http://www.aquacare.de/info/tipps/e1kalkwa.htm check it out
I have the same problem and res sea came out with something and it si suppoed to work. It has very good reivews. Some guy tried to sell me jo's juice and i said no I am going todya to buy some perpermint shrimp.
I bought a peppermint shrimp a few months ago and he took care of them within 3 days. Haven't seen one since. Definitely worth the $5. I was thinking of giving him away after he took care of the problem, but he's a lot of fun to watch so I kept him.
Make sure it's a true peppermint. As with all cleanup crew, I think it also helps to keep him somewhat hungry (he has trouble competing with the fish when it comes to feeding time).
Some people say it's hit or miss, but I bought a peppermint shrimp a few months ago and it took care of the problem within 3 days. Best $5 I've spent (and definitely easier than it would have been to individually inject). Haven't seen an anemone since. I haven't seem him harass any corals either. Make sure it's a true peppermint shrimp. As with all cleanup crew, I think it helps to keep them hungry (in my case, the shrimp can't really compete with the fish during feeding time).
Of course, to avoid aiptasia in the first place, you need to keep your nutrients in check.