I have a one year old male beardie that recently started not wanting to be in his cage. He wants to run around the house then find a place to sleep. I'm worried he's not getting enough UV. I take him out because he climbs the cage walls and runs around his cage making a big mess. He seems to get stressed. He's 21" long, his cage is a 40 gallon long, do you think he needs a bigger area? I would appreciate any suggestions.