Reptile & Amphibian Forums

I'm adding an Under Tank Heater to my gecko's cage due to fluctuations in cage temps the last few days. My question is, how thick does the paper towel substrate need to be to keep the UTH from getting too hot for her? I don't want her getting burned and from what I've read on the forum it seems paper towels are the safest recommendation. FYI the tank is a 10 gal and the UTH is the smallest (for 1-5 gal tanks) so as to only heat 30% of the tank.

THANKS, in advance, for any help!
-----
0.1 Leopard Gecko (Echo)
0.1 Mediterranean House Gecko (Tallulah)
1.1 Cats (Sunny the Bunny & Cosmo)
2.0 Dogs (Gunnar & Ridge)
2.1 Horses (Lakota, Reggie & Tash)
1.0 Betta (Moe)
5 Fancy Goldfish

Its not about how thick the paper towel is. Ussually I put something like a thin rubber mat(between the UTH and tank) that doesnt conduct heat too well(but doesnt melt) to prevent it from getting too hot. I keep my paper towels at 2 sheet layers.
-----
My Site

When i used paper towel with a 5-10 gallon UTH no matter how many sheets i used it got too hot, so when i asked about it here someone reccomended i try switching to slate for a substrate. it works great is easy to clean and was relativly cheep if you add up all the paper towels you'll use in the thirty years your gecko is alive. but to make things easier for cleanup i put a half sheet of towel in his potty area. if you do consider witching to slate, measure your tank and tell the guys at home depot, lowes or whatever home improvement store you go to, that you need the slate to be cut to fit your tank, and they should do it for free. good luck.