>>I think the toughest part of the whole thing will be the door. I'm not sure yet whether I want to try a sliding glass door or not, as I'm not very handy at all.
I prefer sliding doors as they give a much more "open" look to the front of the cage. Not hard to build at all.
>>BTW, do you (or anyone else here, for that matter) have a preferred brand of under the tank heater and thermostat?
I like the Ultratherms sold by The Bean Farm. I believe Cobra Heat Mats are identical.
>>Also, will using an under the tank heat source effect the type of bottom of the cage I will need and the type of substrate used?
Expanded PVC is just about the perfect material for under tank heaters. It's flame resistant, conducts heat well, provides thermal mass, and cleans well. Look for a small piece at local sign shops. You can probably get away with 1/8" thick material for a BP cage.
You might ask for Sintra instead of expanded PVC as it is the most common brand. I have called sign shops and they did not know what expanded PVC was, even though they carried it.
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Current snakes:
1.1 Gonyosoma oxycephala - (Silver/Yellow)
2.2 Gonyosoma oxycephala - (Green)
4.3 Gonyosoma janseni - (Black)