I don't have experience with tubs so I don't know about moving up sizes but I would assume it the same as any other enclosure size... 1/3 of the enclosure should be heated by an UTH.


Not sure if it answers anything but I use ultratherm heat pads from reptile basics or Amazon for two reasons: 1) already assembled and 2) they don't get lava hot like other pads/tape. That doesn't mean you don't need a thermostat just that they aren't insanely hot without one (they still get HOT)

Reptile basics will also assemble heat tape for you to your specifications so if you want to go that route, it's about the same price. Flexwatt, which they don't sell is about equal to their THG tape.

Heat tape assembly guide from them

http://www.reptilebasics.com/thg-heattape-connections