Alright, because this seems to have been missed by a few others, Not all.... But quite a few (*edit* nevermind, it ended up being covered later by most)
What is the temperature of the ROOM you had the tank in? ( what was it at the time?)
What are the WATTAGES of the two bulbs on BOTH heat lamps?
Next! What size UTH did you have on the bottom of the tank, and did you have a thermostat plugged into this to regulate the temperature?
Sounds like things got too hot. Do you have ACCURATE gauges to measure the temps in all areas of the cage? ( A digital Thermometer, and or a Temp gun?) All of these questions, are important.
