I am definately no expert here and there are probably folks with more experience who can give you a tried and true answer but here's what I would do. Get rid of the red light and use a heat pad or ceramic heater. Just like BDs, Tegus can see red light and it may upset his photo period. A timer set to 12-14 hrs of light and heat. Bright white light or even a full spectrum light is important. So is UVB. If you use a florescent fixture, put it as close to him as possible. You can even lay it on the ground next to his basking spot. Basking spot 120F ambient cage temp 80F. A warm bath for about 10 minutes (if wants to stay in let him) about an hour or two after lights on. Keep food in the cage so he can eat when he wants and offer live prey when he is up and about. If he is weak and does not seem normal, a fecal would be in order (yes, I am sure you knew that). If he is losing weight you may want to try force feeding him but that should be a last resort. If you do, Juvi BD pelets are a good source of protien. Soak them good to help in hydration. Try treats like eggs and see how he likes that. They are not warm fuzzy mamals that like to cuddle to feel better. Keep social interaction to a minimum.
good luck
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Bennett

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