Algae or mold?

[Gloworm34]

Is this just algae or white mold? Easy to remove with a pipette but it keeps growing back. TIA!

 

[Rocky998]

Looks like a type of wood fungus. Should be ok. I have had this t in my tanks before. Usually in a few weeks the stuff turns brown and rots slowly... Then I siphon it off or I just let it do whatever. If it worries you, you can take the wood out and rinse it off really well but it may grow back.

 

[Lynnzer]

It's biofilm. I have it myself on newly introduced wood. The excess nutrients leeching out of the wood cause it. It doesn't look nice but it can be rubbed off, or left for the shrimp to eat. My Oto's love it.
Nothing to worry about.