fuzzy pink driftwood

My three pieces of Malaysian driftwood have recently become covered with a light haze of fuzzy pink stuff-algae? Looks a bit like lint with some filaments.

I boiled the driftwood before setting up the tank and the water has not been discolored. The tank is about 6 weeks old, cycled with bio-spira and medium from a friend's tank.

The tanks is 75 gal. There are 8 zebra danios and 6 congo tetras in it. Ammonia, nitrite and nitrate are all at 0. I've been doing 18 gallon water changes every week. There are no live plants. I have a single flourescent bulb, which I have been leaving on from about 7 am to 10 or 11 pm. Since I spotted the pink stuff two days ago, I have been turning the light off while I'm at work. BTW, my light tends to make everything more pink so the stuff may really be a different color.

Any idea what the pink stuff is? At my next water change can I remove the driftwood, scrub it in the old water and put it back in the tank?

I had planned to get another 6 congos this weekend, weather permitting. Would that still be a good idea?

Also I want to get a light that will bring out more blue in the congos, what type would be best?

thanks,
Ellen