Now that it has stated to stay lighter longer I have stopped using UVB lights for my lizards. I've had the UVB light off for my beardie for about 2 weeks and he seems to be doing great. So I moved my Tegu over to the other window and haven't had any problems. These windows get plenty of sunlight all day. I don't think this would be a problem because I guess it simulate how it would be in the "wild". Let me know if you think I should put his light back on his tank. Also I have a 100w basking lamp, I used to have a 150w but we are using it for our chicks right now. I will probably give the Tegu the 150w light back after the chicks go outside. Is 100w good for now though? He can get about a foot away from it. Let me hear your opinions or advice please.