Most reputable forums ..sites like reef sanctuary ...reef frontiers...nano forums...all suggest Kalk paste,joes juice (kalk paste watered down), and or injecting hot water to rid them.
There are those who succeed with peppermint shrimps...and one other bug like creature that actually goes inside them and eats them... I will have to ask my LFS about it again..they carry them.
The one thing I've always wanted to try to do is have a fuge be a Aptasia fuge... have a UV light on the return so it doesn't spread. It would be a great filter if one can keep them in one area.... much easyer than having a duster fuge... cause aptasia are die hards.