how to keep temps at night?

[hoo-t]

would the regular white bulb be fine at night?

No, they need to have a day/night cycle. BPs are nocturnal, so daytime all the time wouldn't work out too well!

As Jason said, if your UTH isn't doing the job, get another to put under there. You might consider getting a bigger one than you have and using the new one for the warm side, and the old one for the cool side.

Steve

edit - oops, sorry Jason , I didn't see your second post.