adesimone1,
I had coral frags that had Aiptasia hitchhikers. I bought some lemon juice from the supermarket (little, plastic yeloow container) and using a small plastic syringe injected about 3 mls (or cc's) into the Aiptasia. It was gone within about 2 days. From what I have read the lemon juice is reef safe, will have minimal effect on water parameters (pH, etc) and is non-toxic. I have also read that peppermint shrimp will eat Aiptasia, however, I did not want to introduce them into my tank.
Good luck...