If you would measure that would be greatly appreciated. I picked up everything else today, it just happened most of it is on sale at Home depot right now too!

Will have it ready for heat tape on Saturday.

I will not be putting it in a heated room, ambient temp is around 70 give or take. Should I use the 11" and will that be enough? Plan to run the hot spot at 90 in the tub. Might have to add sides if the cool side is under 75 as I would like it around 80 at least.

Thanks for all the information!