Congrats on becoming part of the hobby.

As for the UTH, your ball NEEDS heat. I would highly recommend you use the UTH tonight. Too long of exposure to low temps cause RI's which could even lead to death. A pad of aspen should be good for the night, but no longer. Why dont you go and pick up a human heat pad with a thermostat built in? I used one of these for months and it worked great and now im using them for my turk roaches. Also your going to need two identical hides on each side. You dont want your bp having to choose between feeling secure and thermoregulating.

Surface temps for the hot spot can be around 90-92. Just make sure it is only covering 1/3 of the tub. Usually the suggested area covered by the UTH is 1/2 to 1/3 but I would suggest no more than 1/3 since it is uncontrolled. And make sure you have enough holes to release the extra heat that could possibly build up from the uncontrolled UTH.

Congrats on the addition and it soon will not be the only one. But be careful with the uncontrolled UTH, they can be deadly.