Heating Vision Tank?

[Gx3]

I will be purchasing 4 vision tanks (I currently own several and have personally had great luck with them.) The tank I am looking at is 28x24x12 (is this big enough or would it be worth it to go 36x28x18?) My question is, what would be the best way to heat these. I was thinking an undertank heater (hooked up to a thermostat). Then I was thinking about possibly putting some tape on the back (also on a thermostat) so during the winter months I could cut out the bottom heating but keep the ambient temp in the upper 70s with the tape on the side. What do you guys think? I will also have a space heater near the tank set up ( I have a reptile room/guest bedrrom in my house lol) I am trying to get my "breeding set up" all set up at least a month before I get any snakes.

FYI I have bred herps before but never pythons, so this is going to be a new venture for me!

And any tips for getting my set up perfect from you veterans would be greatly appreciated!

[kitedemon]

I have a vision enclosure (24x24x14) model 211. It is currently in a room that is often 68-75ºF the enclosure has a fluorescent light in the 'well' made for it but that is partially covered with insulation. It adds a couple of degrees to the ambient air temps. There is a hot spot uth (controlled by a herpstat pro) and there is heat cable running over the rest of the bottom and about 2 inches up the sides (also controlled by the pro) The UTH is set to 90ºF (interior probe mounting) and the cable is set to 80ºF (also interior mounting)

Currently the room is 70ºF. The hot spot is 90.2ºF the cool end surface temps are 79.8ºF and the ambient air temps are 79.2ºF with the fluorescent off and just a dark blue led lights running.

The day temps gain a touch as the fluorescent lights build some extra heat into the system the surface temps remain the same but the ambient temps will raise during the day by 10 am they will be about 81º at 1 pm they will be about 84-5º and then will start to drop as the room usually starts to cool again some and by 6pm they will be about 83ºF and by 10 pm they will be down to 81º and drop to about 78-9 at the coolest over night. Remember I am speaking of ambient air temps inside the enclosure.