for a baby bearded draogn you can have a 10 gallon tank.. but they're grow out of it fast. 20 gallons are good for youths, but again, will grow out of them. The best suggested size is a 40 gallon breeder. That will fit any dragon.. even adult.
As far as lighting you need a uvb source and a heat source. The best uvb flourescent light you can get is the reptisun 10.0. make sure it's not the reptiGLO, they give off virtually no uvb so are basically useless. Also, be sure you're not talked into any kind of COIL BULB. They irritate your dragons eyes and can cause long term damage. They can also cause seizures. Along side the uvb you need a heat source. I use a household light bulb. You'll need it to be a higher wattage so that that hot side of the tank reaches about 105-110 and the cool side stays at 80ish.
There is a way you can do it all in one... they're called mercury vapor bulbs. The produce heat and have uvb. They can be a little more costly but last up to a year, whereas the reptisuns last for 6 months before needing to be replaced.
If you have any more questions, I'd be happy to answer them and give you good sites for good prices on products. Also if you need any information on feeding, what to feed, when to feed, how to feed, what supplements to use.. substrates.. anythign like that don't hesitate to ask. I'll answer any and all questions. If I don't ahve an answer, someone else here will. bearded dragons can be hard to care for with the wrong information... but with the right information everything is so much easier.
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