Bulk reef supply has a video on exactly this. You should watch it, it explains everything.
I use a daylight compact florescent bulb, which isn't really efficient but I mainly have chaeto for my pods. I also noticed that tumbling chaeto makes it grow about twice as fast
I run one of these on all 3 of my systems and cant tell you how many of my friends and customers also run one. Grows chaeto like crazy and they are only $12!!!!!