So I have a decent sized pink styllo that I lost due to an Alk swing. The colony over time (a couple of weeks) turned black, starting growing coralline algae on the tips, sprouted some other type of short green algae that my tang loves to eat. Looking at the tank last night and low and behold there are half a dozen tips that have turned a pale pink and have short green polyps. It has actually started coming back to life. It wasn't just browned out either. I mean this thing had turned dark gray/ black with coralline growing on it. It blended in with my live rock.

Lesson learned- Don't throw it out just because I think it is dead! go figure