I am very new to this area, but considering the small-sized top, I am wondering if anyone has had success with LED lighting applications for vivaria. I know there have been a lot of advances in this area & from what I've seen with LED applications in marine aquariums, you can get some very high output in a small space with minimal heat.
This one, for example, seems a bit expensive and one strip (the way it is sold) is too long, but I would think it wouldn't be a big trick to crack the case & re-configure it.
http://www.ledtronics.com/ds/plantled/default.asp
Just a thought.
Regardless, I love the idea & the re-purposing of the fixture. Please keep us up to date.
C