Spiderwood turning dark brown?

[semistro]

Hi, I have had a new piece of spiderwood in my tank for about 3 weeks now, and it looks great!
But a few days ago it started to turn dark brown and have a barky texture, I have no idea if it is bad, or if it will spread any further, is it rotting? Is there anyone that has seen this before or knows something about?

This is how it looks like:

There is also some white slime left, the whole wood was covered at first, but I read that it will go away and is not harmfull.

From above the water:

This is how it looked at first:

The tank is only about 3 weeks old so the wood is in there from the start.

Any help is appreciated a lot!
Thanks in advance.

 

[Delapool]

I have had pieces of wood change colour a bit but generally stays firm to touch. I like the last tank photo - looks nice.


Unless the wood is getting bad fungus I usually don't worry too much.