Hey-
I have had my beardie for a little over a year and a half now, and feel like I FINALLY have the hang of temps.
I am using both a probe thermometer and a temp gun (adjusted to wood emissivity) to measure the basking spot, which is a stick, and it reads roughly 103 degrees ( I am still trying to adjust this- under 100 seems too cold, above 110 seems too warm).
My ambient thermometer reads about 86 degrees, and my cool side probe reads about 79 degrees.
For night time- my house is in the low 60's. Usually between 64 and 66 degrees- never warmer. If I leave the tank without heat, it is 64 degrees in the morning.
Is 64 degrees at night too cold?
I know that slightly lower temps, as well as night time drops can lengthen their life span a bit- but too cold is obviously bad, too.
We do keep our house pretty cold, especially at night. I am not sure what all the reasons are (parents house)- it is what we have always done.
One reason though, I think, is that our house is pretty big- 5,500 square feet- with tall ceilings in the main rooms- plus a basement, and a garage door that is opened constantly, as well as the back door- so heating that thoroughly to a toasty 70 might be the issue.
We all just prefer a colder house, too, I think- I prefer cold rooms I can wear sweatshirts in, and sleeping in a cold room under covers.
Do you think 65 degrees F is too cold for a beardie? (at night)
At night my heater doesn't kick on until it gets 63f. That is about what my tanks get to too.
They are quite hardy creatures to be honest, as a general rule of thumb i'd recommend nothing under 60 at night, but truth be told, i've gone lower than that for periods of time with no ill effects that I could notice with my dragons. Once the lights and heat come on, they are back to their normal selves.