Instructions
Position your aquarium heater in your tank in accordance with the instructions for your particular-sized tank. There should be a diagram in the heater instructions that will tell you where to position the heater. However, many heaters are positioned in the corner.
Plug the power cable of the heater into an available power outlet. Verify that the heater is operational by checking to see if the power indicator light on the front of the heater is flashing.
Use the thermostat controller on the heater to turn the temperature setting down until it is so low that the power indicator light turns off.
Let the heater rest for one-half hour. This will help to calibrate the unit.
Adjust the controller slowly so that you increase the temperature of the water. Do this until the indicator light turns back on.
Increase the temperature slowly a couple degrees at a time until you have the desired temperature in the water.
DIY Aquarium Heater Controller
Keeping fish as pets requires more than simply putting them in an aquarium and watching them swim. On top of regular cleaning, an aquarium needs to be kept at the proper temperature in order for the fish inside to thrive. This can be done with a heat controller. This is a unit that is placed in the water of the aquarium and keeps the heat at an appropriate temperature. You can set one of these units up in a matter of minutes.