I use Vision Cages (Models 222, 322, 433)for my Boigas. I feel the added security of only one viewable area gives them less things to stress about. Most of the time they stay up on the bamboo pieces I have set up as perches hidden behinded fake foliage. I do have cork bark curls on the bottom of the cages they will sometimes go under when they are opaque. I use keeper's choice shredded cypress mulch as a substrate.
I heat with flexwatt tape along the bottom and of the side of the cages hooked up to a helix (set to 86 night drop of 78-80).
My snake room is usually around 80 degrees most of the time.
Each cage has a full spectrum light on a timer. The lights are one about 8 hours day.
How do you have the cage heated? Yours might be staying on the floor because they are curling up on the heat source. They also might be hiding under the newspaper because they are stressed.
In my experience Boigas do much better in Vision style cages or Neodesha cages (if you can get them) especially if your are dealing with nervous ill-tempered imports.
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