In the last few weeks my beardie has been dark a lot more often. It's been hard for me to pin down what's causing it. His temps are good. I checked with a digital thermometer. Basking temps are 105. Night time temps are 80. I got him as a baby and he's still in the same enclosure which is 18" x 18" x 18", or about 20 gallons. Now he's about 10" long, but keep in mind he's got a stub tail (like that when I got him). I'm thinking of getting him a large 60 gallon enclosure in a couple months. He eats a little less than before, maybe only 20 crickets per day instead of 30+ before. The UV lamp is a reptisun 10. I dust his food with calcium and vitamins daily. No vit A toxicity cause its beta carotene. The color change seems random. Sometimes he'll be dark, I'll take him out and handle him a bit and then his color will lighten. I put him back and it darkens again. Or the reverse can happen. He also likes to climb the fake rock wall at the back of his enclosure. Its made of styrofoam. Then he just hangs out against the wall for a while like spiderman. Normal? I turn off his lights between 7 and 8pm and turn them on when I get up at 7. He's usually awake and waiting by then. I feed him greens first thing. Poop is normal. I guestimate his age at 6 or 7 months. Substrate is paper towel, which he likes to rip up and bury himself in.