Where's the humidity when you need it?

Hey guys! I'm sure this question has been asked/answered a thousand times already, but I couldn't locate any previous threads.

I have a baby bp (6 mo. old) and I'm having a problem keeping the humidity stable. I have 20 gal. tank with aspen substrate and balled up pieces of newspaper throughout the tank (due to her recent stress issues). I have a pretty large water bowl in the middle of the tank, a uth and 75watt infrared bulb. During her day[light] cycle, the humidity drops almost every hour to around 50% (and sometimes below that). I find myself misting the tank almost every hour (I know, I know, I have nothing better to do than come back to my dorm room between every one of my classes!). The humidity is pretty stable on the cool side, but the hot side is where all the problems are.

I'm guessing it may be the substrate I'm using or maybe the bulb is too powerful. Maybe it's a combination of that and the uth (my temp is usually between 90-93F). I also have a cover made up of aluminum foil (facing downward) and electric tape on the other side.

Any tips/suggestion? Icyss would appreciate it!! :)

Have you ever considered switching to a tub? It's soooo easy to maintain optimum temps and humidity. It would only cost you <$10 and save you lots of frustration.

With my tub (I also live in on-campus housing), I've had problems keeping the humidity -down- :). Other bennies to tubs include: lightweight, easy to clean, and easy to hide from RAs during "inspection" ;) A tub is a lot less conspicuous than a tank, if you're worried about getting "caught".

Then again, if your school's like mine--they aren't exactly thorough with inspections, anyway.

Thank you!! Any recommendations for any forums/sites with good tub setups?