I could try to help you but I would need to know a bit more specific info about your husbandry. temps, humidity, size of tegu, size of cage, diet, is it arg. or colombian? Any detailed info can help. You said it has a fair amount of UVB...what kind and what is the distance from the top of cage to the floor? Also what do you use to dust the crickets? I know that tegus get tremors when they don't have enough calcium but you said this is not the problem so maybe it is something else.
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1.0.0 arg. b/w tegu
1.1.0 white's tree frog- popeye, jack
0.1.0 southern painted turtle- ms.tortle
0.1.0 crested gecko- crimson
1.0.0 pinto hedgehog- dante