Heating Problems with UTH

[abhorrent]

After someone who wanted to give me a free ball python flaked out on me for around a month or so, I decided to give my tax return a run for it's money and bought Ruth.

She seems to be doing alright - I brought her home on Tuesday to a tank that was all set up and was keeping in the humidity, staying constant in temperature, etc. She ate on Friday, as the breeder suggested she would. She pounded two small mice with no hesitation as soon as I removed the hide, and looked like she was interested in more.

I know that has nothing to do with my heating problem, I was just very excited to see her so ready to eat so soon after being introduced to a new tank!

Anyways, onto the actual problem. I had a 5 gallon UTH producing the heat for the carpet, and the temperatures were at 85 warm side and 74 or 75 cool side. That seemed to be a little too low, so I bought a 10 gallon UTH and stuck it to the glass.

Now, when I run it through a rheostat, I can't get the cool side above 75 without having the warm side temperatures near or above 100! If I dial it down to 93-95, she comes out of the cool hide and crawls on top of it to bask at the top of the tank under the light, and she's never gone into the warm hide (assuming it's way too warm).

I still have the 5 gallon UTH, would it be overkill to attach that to the cool side to keep it around 85 and dial the warm down to 93, or should she be okay if she's eating, pooping and starting to explore me when I take her out?

[Gloryhound]

Using the other UTH with a second thermostat is one way of doing it. What type of thermostat are you using? I have had problems creating gradient heat accross a tank using an On / Off type for some reason, but if you do use the second UTH on the cool side set at around 80 - 82 an On/Off type should be fine as long as it is set to 1 degree variance. What type and size of enclosure are you using? Also are both hides the same type? The BP may be choosing the cool side as the hide is better suited for it.

[abhorrent]

I'm using a 10 gallon aquarium with black foamcore taped to the exterior (seemed like a good idea after reading a few of the guides).

The hides are identical, she just doesn't leave the cool hide during the day. I think I'm going to put the smaller UTH on the cool side and dial down the warm side.

[Argentra]

Using a second UTH can help... but first I will suggest that you ditch the rheostat and get a thermostat instead.
Rheostats are great when your room temperature never fluctuates more than one or two degrees... but for most people, they are a nightmare easily solved by getting a controller, or thermostat, for your heat sources.

Here's how I would do it:
If you're a little tight on money, you can order a ZooMed ReptiTemp 500R thermostat from ReptileSupply.com for around $30. That stat may be cheap, but it works. Hook up your warm side UTH to the stat and get it to the right temps, then place that smaller UTH on your cool side and hook it up to that rheostat you have to keep that side down where it should be.
If you can afford to spend a bit, then pick up the ReptiTemp as directed AND a Johnson or Ranco brand thermostat from ReptileBasics.com for around $80. These are the low end of 'the good stuff' - very reliable and the type you can set and forget. Hook your warm side UTH to the Johnson or Ranco and hook up the smaller cool UTH to the ReptiTemp.

Hope that helps.