A Zoo-Med 10-20 Gallon UTH will be perfect for a 15 QT tub. Be sure to solder some holes and moniter your humidity so it's not too high. Do not use a Heat Lamp with a tub.. You definitely won't need the Humidifier anymore. And be sure the tub you use is the latch-type or one you can make secure.

Think that's it.. Tubs are the way to go!