I've been looking for a way to heat water permanently to a certain temperature. I was afraid of having to buy expensive equipment or myself to tinker what, until I stumbled by chance on the aquarium heater. I am not come to it! Certainly works quite outstanding, the temperature is easy and easy to read set of 20-34 degrees. The appliance heats then from time to time, is thus a thermometer in it, which incidentally measures fairly accurately. Have all been tested with a normal "mercury thermometer". The variance is not more than 0.5 degrees, depending also how much is added to that water in motion. All in all: Highly recommended!
