>it is run in the bottom of the cage or what? if so wouldn't that also heat the top of the cage stacked below it?
If you go underneath the cage tape it directly to the bottom. Depending on how your cages are set up foilfaced espanded polystyrene can be placed underneath the cage. this will help reflect heat up into the cage while insulating the cage below. Some people recommend an airspace but that may not be possible.
>or would it go on the back in which case how do you protect the animals from coming into direct with it or it from water/humidity damage?
I don't use visions or I may have been more helpful. However, My current cages use heat tape on the backs of the cages. This piece of heat tape is taped with foil or in my case glass cloth tape (very expensive stick with the foil). This is on the backside outside the cage to clarify it a bit. I also cover this heat tape with Reflectix a foil coated bubble wrap available at Ace hardware and Menards. This reflects heat in the cage from tha back and works really well in my situation. I don't have visions so this is all a helpful tip not a recommendation for success.
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Jeremy
"I am become death, the destroyer of worlds" July 16, 1945 Robert Oppenheimer
1.1 Double Het "Sharp" Snow RTB's
1.1 Hypomelenistic RTB's
0.2 Pastel Hypo RTB's
2.0 Double Het Stripe Albino RTB's
0.1 Suriname RTB
0.1 Anerthrystic RTB
1.0 Ball Python
1.1 Rhinoceros Iguana's
1.0 Green Iguana
1.1 Cream Golden Retrieviers
1.0 Pomeriaian
0.3 Catus Terribilis
0.1 Spouse
0.0.1 Youth -coming soon-