Black stuff on green tree

[turfgrass]

I couldn't get a good picture of it, but it looks like charcoal. I noticed it a few months ago and just scraped most of it off. Well it's back and growing uo the trunk of the tree. Should I frag it and discard the trunk? Thanks in advance.

 

[Greg Hiller]

I wouldn't discard it. It might be a bit of cyanobacteria growing on a rough section of the tissue of the coral. I'd try and blow, or brush it off every so often, but wouldn't sweat it otherwise.

 

[turfgrass]

I just cut it up into three sections. Here is a cross section of the trunk. The black stuff not only grew on the surface, but also entered the coral tissue.

 

[turfgrass]

I did try brushing it, but some of the stuff took anchor.

 

[OceanGuy]

I brush mine gently with a soft toothbrush which I've taped to a dowel.
It is a useful tool to get the black dots off of the green tree. I think some of my fine particles of charcoal get blown out through the return pump.
When the black dots are on the green tree, it doesn't come out as much. I think it annoys it.

Good luck with it. Let me know if you find it is something different.

 

[qazplm25]

This exact same thing happened to mine. But then I fragged and moved it to another place in my tank and it dissapeared. I have no clue what it was.