Is an Under Tank Heater enough for my leo even when it gets cold enough in my apartment that I need a heavy comforter to be warm enough in bed?

What temperature does your room get down to?

That's pretty impossible to say when we don't know what temp it gets to!

Have you got a thermometer in your gecko's tank? - it would be wise to have one, otherwise you can never be sure that the temps are right. Over winter it might be wise to use a spot bulb, with a Under Tank Heater for background heat at night. We use spot bulbs during the day, which gives a hot spot of 88-90F and allows for a cooler end. At night we don't use anything, as at the moment temps are ok, and the snakes' room is pretty warm all round! But when it starts getting really cold we might need to use a Under Tank Heater through the nights, we did last year.

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"If you know everything you may as well blow your brains out because the reason for existence is to learn more everyday." - Mark O'Shea, 2004

I'm not sure what the temperature gets to in my room, but some nights in the winter it'll probably get to below 60 degrees. I can't really say more than that, since I'm not sure. And I just got my leo in June, so I don't know how cold his tank will be...I think I'll get a night spot light just in case, though. I'm in Vermont, so it gets pretty darn cold.

Temperature is nothing to guess at. Go to walmart and get you a digital thermometer. Cost about 12 bucks. It has a remote probe and a minimum/maximum feature that will tell you exactly how high and how low the temperature gets. I suspect that you will need an additional heat source. The Under Tank Heater will provide belly heat but the animal will still be breathing cold air.

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Merlin,
What's Life Without A Little Magic!