you can keep them at the same temp but i like to lower the temps because its more natural for them. It gets cold in the desert so it should fall a little in there tank aswell. its really up to you but make sure if you have a white bulb that it gets turned off because than it will seem like daytime to them ALL the time and its not good for there life cycle. If you use a red bulb it doesnt matter because they cannot see the red colour so it seems to be night time when you turn your room light off and when its on they see it daytime. Some people use both a white bulb and a red bulb and switch the times. Using the red for night and the white for day. Its really all up to you

hope this helped