The Reptile Basics 28 watt would probably be fine for your 2' cubes. But for the same money you can get the 40 watt. I'm not sure what your winter ambient temps are so the extra wattage may come in handy. Either way you should use a thermostat to control temps. The 40 watts could also be used later if you decide you need bigger enclosures as you BRBs grow. These have been tested on cages up to 2' x 6' x 1' and have been more than adequate.
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BigT
There is a difference between ignorance and stupidity. The ignorant can be taught, stupidity is beyond our control.
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