As far as for shedding. Long soaks are the best to help him shed a little bit faster, or at least make it feel a little bit better. Some dragons during shed get a bit grumpy, and won't eat as much as usual. Can you blame them that must be very uncomfortable.
Being dark colored can mean a few things. When they are nervous or excited they might display a darker color. They may also do this to raise their body temperature dark colors hold heat better then light colors. Ever notice when they sleep they get very light?
One thing I will suggest is to get one of those lizard leashes cause all it takes is one bird, or plane to fly over head and you might have a very defensive dragon on your hands, scary if you never had this happen to you. Glad he liked it though. The leash is just for safety.
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