It really depends on your setup. In mine, the UVB light and basking lamp are right next to each other. The basking spot is about 8 inches from the lights. If they climb on the top ledge (which they do all the time), they can get within 1" of all of the lights.
Also, be sure that your thermometer is right in the basking spot. It can be quite a differnece! Mine was down to the side along the glass and partially under a rock at one point. It registered over 10 degrees cooler!
I run my lights as follows:
The UVA/UVB lights are on a timer. They come on a little before 7:00, and go off at 9:00 at night. The heat lamp is not on a timer. I usually turn it on about 7:00, and off areound 8:00. I also leave it off if I am going to be gone for a day or two. With the lower temps, the lizards won't be active and won't need to eat.
Of course, you have to remember! Yesterday, I forgot to turn it on. I got home from work, and the lizards were still in their den. I turned on the heat lamp, and Amon was out in less than five minutes, soaking up the heat. Amaunette joined him shortly after. To make up for it, I left the heat lamp on until about 10:00. They promptly went to bed when I shut it off.
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1.0 Common Snapping Turtle (Goliath)
1.0 Brown Anole (Anubis)
1.0 Green Anole (Baal)
1.1 Great Basin Collared Lizards (Amon, Amaunette)
0.1 Chilean Rose Hair Tarantula (Spiega)
1.0 Chesapeake Bay Retriever (Logan)
0.1 Spoiled Mutt (Storm)