Hey what does it mean when they sit with mouth open is it a problem?

It can mean a variety of things. The most common problems associated with that are sores in the mouth, a respiratory infection, or the temperature is too high. None are good.

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+5 bonus points to whoever finds me a job!

"Eagles may soar, but weasels don't get sucked into jet engines." - John Benfield

Matts absolutely correct. Give us a little background on your set up, the husbandry, temps etc.

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MARSHA

:D I'm smiling because I have no idea whats going on!

If the dragon is otherwise healthy and eating well, it's probably way too hot and dry. He likely needs more water in the tank, and more humidity in the air. However, there's no way to be sure. Background information would definitely be good to have, but if the dragon isn't eating well, or looks pale, a visit to the vet is your best bet.

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"Let's eat, Grandpa!"
"Let's eat Grandpa!"

Punctuation. It saves lives.