Is my log growing mold?

So today I had a little mishap with a crack forming in my old tank so I’m in the process of moving everything to a new tank. However when I went to take this log out of the old tank I noticed all these white and black dots on it as well as a few fuzzy bits. I’ve had this log in there for about 7 months and I have a bristle nose pleco that loves to suck on it. I’m concerned this is mold and I don’t want my fish to get sick. Any help or advice would be appreciated, thanks!