Any idea what's going on with this "fungus"

[ThaGlasMan1]

 

[hzheng33]

View attachment 93038

That’s black hair algae I think

 

[shimshimshinil]

How long have you had the driftwood? Mopani is notorious for having a lot of sugar. It's a very common fungus on mopani wood that's eating the sugar. Eventually your bacteria will outcompete it and some fish eat it. I think some people just vacuum it out slowly.

 

[acandoit]

I would vote for the fungus over the black hair. I have the black hair and it is a bit different than this

 

[scuba steve]

If that's a new piece, it's a very common. Ottos and a number of fish will eat it or it'll go away on its own after a few weeks