It's about time someone came up with a preset turtle tank heater, and it was Zoo Med to the rescue. The all new Zoo Med Turtle Therm Heater is the answer you are looking for. It's so easy to set up just suction cup "Supplied" the heater to the back glass or side glass making sure the heater will be located 100% under water then plug it in. Your done! This heater will automatically bring your turtles water to a comfortable 78 degrees then shut off until the temperature drops again. Heater features a built in temperature display so you will always know what the waters temperature is at. Available in two sizes: 50 watt for up to 15 gallons of water and a 100 watt size for up to 30 gallons of turtle tank water.