Driftwood & a gritty dark coating

So I found driftwood by the lake last summer. No clue what type of wood it is, but I boiled it for hours & hours. I scrubbed it, I washed it. When it went into the tank it sank no problem. Months later it started looking dark, almost black. I took it out, and using a toothbrush managed to scrub off the gritty coating. The grittty coating almost brushed off with little effort.

What was it that appeared on the driftwood? Will I see it again? Was it something from in the tank finding its way onto the driftwood, or from within the driftwood working its way out.

 

No replies ... maybe it's algae? Is there a gritty almost sand-like algae that can form in tanks and on driftwood? This coating on the driftwood has come back, and again srcubs off with no problem.

I'm thinking next step might be video to show you what's happening. I take the driftwood out of the tank, if I'm scrubbing something off, it might as well be outside the tank than in.

There was a moment, however, where I started to brush it while it was in the tank, and I wonder if it's related to tannis?

 

Any photos? Was the wood de-barked? Dark pieces coming off could be rotting.

 

No bark.
Driftwood was added about Sept 2011. Clean pictures from Nov 2011, dirty pictures from Jan of 2012. I've scrubbed the driftwood clean twice since then.
A new addition in my tank this year is adding C02 via excel. Plants are doing better, less algae.

 

Looks like algae as it's on the plants too. Looking at that plant I'd say there's an imbalance in your tank.

CO2 will help if your lights are high and you use fertilizer.

Another note. Are you using root tablets to feed that plant? If not, get some and place directly under plants. Root tabs will help with that yellowing on the leaves.

 

Here's a more recent photo, with Excel being used daily.


This is from today, after the most recent scrub of the driftwood.

I'm saving my pennies for the C02 kit, I tried the DIY, but it didn't work too well. I think I failed on the diffusing part. I'll look into root tabs.

 

Pretty good.

I noticed that you have Roseline sharks in your tank....they are one my favorites.

 

Thanks.

 

*bump*

I've added root tabs, they do make a difference, still on the hunt to add C02.

I'm still getting that coating on the driftwood. I took it out during my cleaning today, lightly brush it, and I would almost guess it's tannis. The water rinsing the driftwood during the scrub almost looked like tea.

Is it algae or tannis? It's not chaning the water in the tank at all, so I'm still thinking algae.