How to lower humidity

Alright folks, I've done some research, and tried some things, but the humidity in Will's tub stays too high no matter what I try.
He's in a roughly 40 by 12 Sterilite tub with multiple air holes, with a cool side of 75 (which I am working on) and a warm side of 92. His heat source is a foot of 11" flexwatt, and he is housed on newspaper. I don't keep his water bowl in all the time because of the excess humidity, but he stays well hydrated.
The problem is that his humidity seems to stay between 60 and 90%, with an average of around 78. Our house's humidity is relatively high, usually around 61 percent. Any idea what I'm doing wrong?

mores holes

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78 is okay...btw not bad a little high though

Smaller water bowl

X2 on the more holes and smaller water dish.

If there are plenty of holes the high humidity is no problem. High humidity is usually a sign of poor ventilation (problem) but if your house is naturally humid it is just going to lead to perfect sheds! I would leave a small water bowl in all the time in case he gets thirsty.

I wouldn't stress over it quite yet if I were you. Give it time, see how he sheds and feeds. If he does both with no problem, skin seems fine, then stick with it! Lucky you with your high ambient home humidity. :)

-Jen