Hi, I'm new here. My daughter has a Juvenile (6 months) Beardie named Churro. He was given to her in a 10 gallon tank. We have a 20 gallon tank that we're not using and I wanted to know what size hood and Uvb light should we get. Also, should it go on top or inside the tank? It's 30" L x 15" H x 12" W.