I think I said it wrong. If you can maintain the temps of ambient air ~86 degrees, basking spot 88-94 degrees and a cool side of 78-84, then you don't need the heat pad. But if your room is a cool 72 or so with the A/c on, then no you're probably gonna want an UTH to maintain proper temps. At the end of the day, that's all it is...maintaining temps. Doesn't matter how, as long as they are constant. Most folks with tanks will use a UTH+CHE, or a UTH+Day/Night bulb.