Is My Bog Wood Rotting?

Is my bog wood rotting its like dust on the top of it I have 2 peices of bog wood and one has it considerably more but could be due to its closer to the surface. And if it is rotting is it harmful and what should I do? I have 5 zebra danios in which are there temporally as try where there to cycle my tank and have tested for 2 weeks and had 0 ammonia and nitrite and going to add a breeding trio or pair to the tank it's 120 litre tank and can someone also recommend what fish I could breed I want a fish that cares for there young.

It looks like algae to me, i get the same thing and i just take it out the take scrub it and rinse it and its all gone.

I would add some snails or algae eaters as I think it is just fungus covering your wood. Some fish love it if I am not mistaken (not 100%) snails should eat that up.

Nah it's not rotting and it's not harmful either (It's a bacterial growth), mine did this in my new tank about two weeks ago, I just went at it with an aquarium specific designated tooth brush to dislodge it all while still in the tank, a small amount reappeared several days later, and just repeated the toothbrush attack and after that no sign at all of any more growth

Ill go get a few plecos today see if they want to get rid of it if not ill try the toothbrush method! Thanks for the advice.

Here's my tank.

make sure you get the right kinda, normal plecos get 2 feet long, I would go with some ottos or bristlenose plecos.

Don't matter what one I get ill just put it in a larger tank when it gets bigger only do small ones in the LPS.

ok cool.