1. Are they pretty friendly towards people?
They can be very people friendly. It does depend on your individual dragon though. No matter how much time you spend with it I have heard of the occasional vicious SOB, but it's like that in all species even human.
2. What kind of substrate can I use safely?
Newspaper, paper towels or none is the safest for babies. There is a big debate on what is safe for adults, most would agree to avoid things that could potentially block them up like; calci-sand, fish tanks gravel, dirt, etc. Reptile carpet works pretty well (and you can wash it) as long as you throw it away when it starts to frey because the strings can get wrapped around the toes and cut them off.
3. How many adults can I put in a 55 gallon? That is pretty much is biggest I can get
Safest number is 1, although for breeding purposes you could probably get away with a pair if it's a 55 long and not tall.
When you get ready to buy remember a quality animal from a quality breeder makes a big difference.
Sean
Heart Mountain Herps
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