I have a 20 long with two lamps (one day and one night. Day is 100 watts, night is 75), I have a rocky style hide under the lamp and a log on the cool side. The substrate is coconut husk (the fine soil type). The water bowl is on the cool side over a small sticky heat pad that's outside the tank on the bottom. I have a strip thermometer for temps and a humidity gauge on the side in the middle.