My rack uses heat rope, not tape, but it does the same job and sits in grooves built into the shelves underneath the tubs. The tape heats up to warm the bottom of the tub, and the temp probe keeps the surface inside the tub at a preset constant temperature. I have a warm and cool side in each tub....the warm side is at 90 degrees, (heat rope directly beneath), the cool around 80, (no heat rope under that side). Between them the air temp maintains at around 80-85. The digital Herpstat Pro also allows me to program nightly or seasonal cool down cycles if desired. The shelves of the rack unit are ventilated to allow air flow. Unless you have a room that maintains constant temps in the high 80's/low 90's you have to have some kind of artificial temperature control to safely keep reptiles, thus the need for a temp controlled rack system. Ball pythons don't need radiant (overhead) heat and UV exposure like many lizards do, so the belly heat supplied by a rack system is what seems to work best with them.
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