One of my pieces of live rock has some kind of red encrusting growth on it that is growing vey slowly. There are some button polyps and zoos on the same rock and when the stuff is makes its way around the base of these they elongate and don't seem to like it. I can peel away some pieces of it, but some of it won't peel off. It is dark reddish-brown and has a velvety texture to it. The tank has been setup for two years and the stuff has been there for a long time I don't think it is cyano, that's suppose to be slimey, right?

Can anybody tell me what it is and what I should do about it?