Dendrophylax lindeni and Mold

[FlyingBrunswick]

I was recently gifted a few Ghost orchids and after reading as much as I could find I've run into a little problem.

I have each set up in a different "environment" mainly as an experiment to see what they like. The consensus seems to be that Ghosties should be grown above stagnant water with little or no air circulation and high humidity. My ghost being kept this way seems to be developing mold on it's mount that is steadily creeping towards my baby! The terrarium is set to 86F during the day, 68F at night with 78% humidity and a humidifier on a timer 7 times a day for five minutes. It receives about 2000FC for most of the day.

Though the Ghostie looks happy (so far!) the mold is worrying me. Which is the best method to deal with mold in these conditions, and is it possible to prevent it (other than adding airflow)? Are my conditions off?

What do others that are growing these do about mold?