believe it or not, but anemones are really considered reef safe. While many here have them in reefs (including myself) they should be given plenty of space to avoid chemical warefare. Also, while some some clown have been known to adpot certain corals as hosts (torch coral, long tenticle plate coral, hammer coral, etc.) it is rare and should not be depended on. It should actually be discouraged as the clown's agressive routing can irritate the coral, in some cases causing death. FWIW, a clown fish does not need a host to be happy in captivity.
Some people are like slinkies...they serve no real purpose yet can still bring a smile to your face when you push them down the stairs!:p
Have a great day! Brian