contact the breeder you got him from. The main reason for this is so that you can continue doing what they did so stress will be minimized.
That said, it depends on your house temps and the ventilation and air flow around the cage as well as the cage size itself. You need a heat light and UVB light. provide 12 hours of light and no light at night. if temps drop below 70, you can use a ceramic heater to warm the cage not a light. Provide a place to hide too.
Make sure you test any light for 12 hours to make sure you dont cook your tegu!!!!
more info
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Bennett

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