For about a month now this brown cyst-like thing has been growing. I've been in the hobby for most of my life, but just returned from a 15 year break. I decided to get back into it by establishing a 13 gallon micro in my apartment. Chemistry is all within normals, and I've been doing alright(ish) so far. I've never seen anything like this bump before. It almost looks like a cyst of some kind. Can anyone identify it? It doesn't seem to be growing very fast. The coral still eats well when fed.
