Hard to tell in the pic but I had something like that years ago. They started out just like that and then ended up being an algae bloom. This algae was pretty aggressive, can’t recall getting a positive I’d on what it was... At the base of each start was almost like a little calcium deposit or rock. I ended up employing a yellow tang he went to town on it. Cleaned it up entirely in a matter of a week or so. This started out pretty much colorless and then ended up being almost a yellow to light green algae. I’d say it was almost white when it started out though. Looked very similar. My tank was pretty new then though. Is it possible you’re going through something similar?
