grayishblack hair like growths on drift wood?

  • We are currently upgrading MFK. thanks! -neo
Sounds like a fungus.

Primafix for 7 days after you take the wood out hit it with the hose on full blast and a bristly scrub brush.
 
could be hair or beard algae. google pics of those and you may be able to tell what you have
 
Could definitely also be harmless brush algae.

The treatment will not hurt anything if it is not a fungus.
 
I suppose you could take the driftwood out, scrub it, and let the algae dessicate to death. That's what I do with my rocks when they grow too much algae.
 
I have something similar on the back of a piece of oak that I collected myself, it has not caused any problems and the water chemistry is fine so I just let it be.
 
I had the same problem.
 
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