As for your first question, the reason why adult beardies seem to be on the fat side is because unlike out in the wild, in captivity they are getting more vitamins and minerals then they would out in the wild. The best bet is to stay with only veggies as a diet for an adult and only use meat as a treat every now and then. Also, giving it to much supplements can cause weight gain as well as various health problems. Usually, with adult dragons, you can go every other day or so dusting the food with supplements. However, pinkies are VERY fattening and should be only fed on very rare occasions. Like, once or twice a year. If you dun want your dragon to be overweight, I suggest taking pinkies out of it's diet and as stated before, stick with a veggie diet as an adult. Keep in mind that out in the wild, it's only the babies who eat bugs. When they get older, their diet is mostly plant matter.
As for your second question, there is a website out there that gives you the best ideal setup for a beardie. I seemed to have lost the link though so hopefully someone else out there has it to give ya.
Your third question is one that I asked too and made me change what I was using quickly. NEVER use Calci-Sand, Repti-Sand, or any other sand as bedding. (Playground sand is ok, but only for adult beardies and as long as you don't feed the prey, dropping it onto the sand where the beardie can easily catch a few grains)Yes, it looks pretty but it's expensive and most importantly it can cause imapction which can lead to death. Even those bags that say they are "vet reccommened" aren't healthy. I tested my Zoo Med's Calci Sand and the sand didn't dissolve in water like the bag said it did. I wish I could remember who told me about that test on here, but yea... since then I switched to newspaper and believe it or not, it work's out perfectly. Very absorbent, easy to clean up, and very cheap. =D Now yes, black and white isn't pretty but it's safe. There are also many other safe beddings to use that are cheap. Papertowels, cage liners, and others I'm sure that I can't name off the top of my head right now.
Hopefully that helps. ^^
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Bearded Dragon x1(Scamp)
Cats x3 (Lelu, Hera, Nite)
Horse x1 (Renegade)
