I agree that peppermints work the best, but you have to be careful with them. They can sometimes wreak havoc on some corals after the aiptasia. They are known to sometimes go after zoanthids, and in my own tank they constantly harrassed my duncan and killed several Tridacna clams. This is also true of any of the other "natural" solutions like the copperband, kliens, auriga, and racoon butterflies (although I must say I've never heard of using foxfaces before, to my knowledge they are typically herbivores). Some people will have a certain kind of butterfly that never nips at other corals, while others with the exact same kind of butterfly will report that it went straight for their coral and never once touched the aiptasia. This is not to say that "natural" solutions don't work, but I'm just saying be forewarned. FWIW I've also had good success with the kalk injections, but its not always an easy process.