humidity and lighting for my pacman

[jabasmama]

Hi. I am having a hard time keeping the humidity and temp up in my tank. It is a 10 gal with a uth on the side. I might use a 40W blue bulb on top of the screen if the temp doesn't go up. My temp is currently 70 and humidity is around 60. Also, this might be a silly question (I'm new!) But should I be misting with warm water? And should I treat water that comes from my water dispenser on my fridge...its filtered.
Thanks!