Ways to lower humidity without drilling holes?

[redshepherd]

I'm using eco earth coco fiber substrate, which I understand is supposed to be very good at holding humidity... so I've had it air dry out completely before putting it into the enclosure. And the humidity is still 90%. And it just stays around 90% or even over 90.

My house seems to just be humid, as the humidity is even 60~65% even out in the open. Cake is in a new exo-terra glass tank with a screen top, and the humidity is perfect in there, no wet paper towels or extra work needed. LOL

Is there a way to lower humidity in my PVC enclosure without drilling a million holes?