I've had my year-old BP in a glass tank enclosure since I got him, and as you can imagine I've had issues maintaining humidity.

Well as a stopgap until his permanent AP enclosure gets here in however many months from now, I've set up a plastic tub enclosure yesterday. Temperatures are all set correctly (90 degree warm side with a gradual gradient from 80 in the middle to mid 70's on the other end), but the humidity is absurd. There's two thermometer/hydrometers in there and the latter has been "maxed out" (they stop counting numbers and just say HH when the humidity goes beyond 99%) for close to 24 hours now. This would be great if this was for a baby Brazilian rainbow boa but alas I only have a BP. The substrate is coconut Reptichip and I ended up using slightly more than what was needed, plus it's freshly hydrated so it's still trapping moisture and such, but the problem is it's just too much and if it doesn't go down soon I'm worried about scale rot. Though I should preface this by saying he's not in the tub yet, I've set everything up so his old setup can still run while I test the new one to ensure everything's stable and safe over several days before moving him.

So question is, what should I do? First thing I can think of is adding more air holes on the lid of the tub (there's currently just a row along the sides). Could also just leave the lid off but that obviously won't be a long-term solution for when I clean it out and add new substrate since he'll be living in it by then.