Lots of new chondro keepers, even reptile keepers from other disciplines, will often believe that tree pythons (or any arboreal snake for that matter) will need a tall cage. I can certainly understand the logic behind the thought: “trees are tall and these snakes need to be high in a tree to feel safe”. However, that has been proven false for over a decade now, at least for chondros.
Chondros actually do rather well in captivity in low horizontal cages, so long as there are plenty of branches to utilize. They perch off the ground to sleep, as well as hunt, but will regularly crawl around on the cage floor as they cruise/explore their environment. The benefits to lower cages are two-fold. First, they don’t take up as much space, which is handy when housing lots of animals. Second, it is much easier to set up a temperature gradient (important for adult chondros) in a horizontal cage.
In this diagram, you can see how the radiant heat panel generates heat, and how the heat is distributed. The heat panel must be mounted in the center of the top, creating a vertical distribution of heat layers. Because of perch placement, the temperatures at each perch level will be pretty much fixed within the heat distribution zone. This means the snake has only 3 different fixed temperatures to choose from, and has less ability to adjust incrementally.
In the second diagram below, you can see that on a single perch the snake can “tune” its temperature based on where on the perch he/she sits. Slight movements left or right on the perch can offer incremental heat adjustments of 1 degree or less. It becomes easy to see how this second layout offers more options to the snake for selecting the appropriate temperature.