Melamine holds heat extremely well, and the white inside the cages reflect light as well. For both the 3x2x2 and the 4x2x2 I use 100 watt Zoomed Powersun flood bulbs for heat/UVB, and a regular fluorescent light for added light the length of the enclosures. I'm able to get sufficeint basking spots in both size cages with these bulbs. Just got to adjust the basking spot to get the needed surface temps. Never had to lift a basking spot more than six inches off the ground to reach the right temps..Also if you use melamine make sure to use vents on the sides or back. You can see the vents i used in the pics down the forum. Also I read your post above, and would advise not to keep adult male, and females together. Males will breed non stop if they had the chance, I know mine would. The female can become really stressed by this and will not be happy, or healthy. You will have a non stop flood of eggs, and with the way these dragons produce this wopuld not be a good thing at all. 4x2x2 would be great for one adult beardie. I even keep single males in 3x2x2 with nice space for them. I keep female pairs in 4x2x2 as well. Good luck, and when ever buyiong a pair of females always go into it planning to keep them seperate. Sometimes they live well with others, some times no matter what you do some dragons just need to be housed alone.
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Mystical Dragons