I will also say that the soil mix has some compost in it which would invite decomposers. I had to leave my plants alone for 3 days when I went to the Summer Camp festival over the weekend and some grew tall enough to come in contact with the fluorescent tubes, but I don't think that would cause this problem.

The "pests" are very tiny "white" insects that move pretty quickly for their size and do not jump when disturbed, or so that I have seen. They also do not exhibit a larval like build. They do not come to the top of the soil unless their is some form of disturbance. My camera can't get a clear shot of the little rascals in action, but I might try to catch a few and get a diagnosis from someone around here. My soil has been pretty moist recently, so I intend to let the medium dry thoroughly before the next watering. Here are a few pictures to help out.