Boy oh boy. I tried vinegar and they practically melted off the rock. I injected them and within a few hours they were completely dead and starting to disintegrate. I think I found the cure. Thanks for the help everyone.
Very True - I had a growing Majano problem in my DT. I bought an Auriga (Threadfin) Butterfly fish and after a month or two they were virtually eradicated. The down side, I don't think anything eats these exclusively. So as collateral damage all our Pulzing Xenia was devoured as well as a softball sized Frogspawn. C'est la Vive, I suppose.They are fine for non-coral tanks.
Some butterfly fish will eat them.