Hair Algae on old live rock

[J. Dowdy]

I recently set up a new 20G and I used some OLD Live rock that has been dry for over two years, I set the tank up last night to cycle and I wake up this morning after the cloudiness went away, and there is hair algae on one of the rocks that is still green and looks healthy? How is this possible I know it didn’t get this big overnight, or did it? I scrubbed these rocks with RO/DI Water and a stiff bristle brush and let them dry for another week after that before using them. I really don’t think I missed seeing a good size chunk of hair algae on the rock.

 

[RJinPV]

Just like a classic horror film!

I didn't think this was possible either...do you pics to prove it?

 

[J. Dowdy]

I don’t have a close up one, I’ll take it when I’m home from work

 

[J. Dowdy]

And even after thinking about it, it doesn’t even look like hair algae, it’s too stringy. It doesn’t have that velvet look to it