You actually might be better having both lights at one end. You want to have a temperature gradient. In plain english,.. one end is cooler than the other. This allows the snake to adjust its body temperature as needed by moving from the warm end to the cool end. Having one end 80-85 degrees and the other about 75 is ideal however you may be hard pressed to achieve this in that small of a tank. What wattage of light bulb are you using in the 2 lamps?