This was not on the rock when i put it in with all the rest of the rock 6 weeks ago, at least not big enough to notice. I noticed it like 3 weeks ago and it has like doubled in size since. Anybody know what it is?
almost looks like it might be a little piece of a leather coral of some sort regrowing, or a calcerous algae some sort of description as to texture or feel would be a great help in analyzing it.