I am in the process of trying boiling Vinegar.  I went to my local pharmacy and purchased some syringes.  I chose the Vinegar patch over injecting them with Kalk wasser because I was concerned about the Kalk clogging the syringe.
So far, second night, I have had mixed results.  After injecting 3, two fell off the rock by the next day and one is shriveled up.  I injected that third one again tonight as well as two others.  I have quite a few so I guess I will just have to be patient.  
I originally got rid of most of them by trading my live rock at a local fish/reef store.