Definitly NOT a 40 gal.!!! The minimum an adult beardie should be in is 55 gal. I have mine in a 55 and I also let him run in my home a couple of times a week so he can get exercise and stimulation.
You can't always believe what you read. I have read many books/articles about beardies love for climbing. My beardie doesn't like to climb or be up high. He has tried to break his neck several times by jumping from the back of the couch so he could be on the floor. He never climbs. Not even in his aquarium (where I have placed branches of different heights. He likes to be verticle, but always with his back feet on the ground. Strange.
Good luck.
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Hangin with the Herps
ZZ 