ZooMed UTH: Small or Medium??

I'm not sure what size to get for Stanley's 15 gallon tank. The small is for 10-20 gallons, but it is only 6" x 8"... This seems too tiny to me! The medium is 12" x 8", which seems like a better size, but it says it is for 30-40 gallon tanks. I ordered both of them through the pet store I work at, so I can take them home to compare and see which works best. Which size should I get? I have a dimmer to control the temps.

You'll want to go by measurement rather than what they label them as. They should cover 1/3 of your tank, sometimes a lil bigger than a 1/3 is fine. But any larger or any smaller, you may have difficulties getting the heating right.

So measure them and see how big they'll cover for your particular tank size

mardy is right you just need to see which one takes up 1/3rd of the tank floor, i had gotten a 20 gal from a thrift store recently and i have turned it on its side and am converting it into a front opening tank. i had ordered a cobra heat mat that was for 50 to 60 gal tank (i figured i would sit the tank half on it if it was to big) but because of how much bigger the tank floor is now that it is on its side the 50 to 60 gal fits it just perfectly. so it all depends on what fits the floor space ^.^

So which one did you go with? I have a 20 gal long and am using the 10 - 20 gal UTH but I feel like its too small. Half of his humid hide is on the UTH so that takes up some of the heat space too. It seems like he is always inside his humid hide or just outside the door way to the humid hide on the heat mat. He does explore the tank frequently I just feel like maybe he wants more heat space. Anyway just curious what you went with because I'm probably going to get the bigger size.

Hi,

I have the 20 gallon long tank and it measures 30" by 12" so I went with the medium UTH which at 12"x8" is 2 inches bigger than 1/3 of the tank. My Leo doesn't seem to mind and I haven't had any issues maintaining a hot side and a cool side. Measure the floor of your tank and see which pad comes closest to covering 1/3 of the surface.

Yup medium is what you want if you got the standard 30x12x12 long 20 gallon tank.

For my 15 gallon, I ended up going with the medium. It's just the right size for me to put the warm hide and half of the humid hide on it. So far, Stanley loves it!

Stellar. Thank you I am going to get the bigger one.