All of these little issues must have you frustrated! I've never used a RHP, but I was under the same impression as you; that they would create a nice hotspot...
Either way, ambient temps work great! I keep my Snake room at 86-88 and every Snake eats, so you shouldn't have any issues.
I have also noticed high humidity in my custom box, but with both it comes down to ventilation. So maybe do what you said and add some more vents? Or keep a low humidity substrate.
What size hide or that for the BCI?
Have they dropped their water bowls yet
Those Pvc cages look great though! Where they the custom ones you mentioned someone building for you?
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