If you're new to putting up your own home aquarium, you're probably aware that there are several items to purchase. An is one of these products. You may have heard that an aquarium requires more than one heater, depending on where you looked or how much research you did. Some argue that you only need one heater because else the two would continually quarrel. It is, however, a learning experience, as is everything. Everyone has their own method of putting together a tank and what they believe is optimal for day-to-day operations. While there is no right or wrong answer to this topic, there are benefits and downsides to consider.
About Aquarium Heaters
Aquarium heaters are not difficult to use. They are programmed to switch on (start heating) when the water temperature falls below a specified threshold, then turn off when the threshold is reached. They don't seem to notice or care whether the aquarium system has another heater. When specified temperatures are attained, they simply switch on and off.
Advantages vs. Disadvantages
Having more than one heater in an aquarium has several obvious advantages. If the aquarium is in a chilly environment and the water temperature dips, a second heater will help enhance the heat produced and assist raise the water temperature. If your system has two heaters, you might want to set the second heater to turn on a degree or two lower than the primary heater.
Another advantage of having two aquarium heaters is that if one fails to switch on (for example, if one burns out), the second will keep the aquarium at the proper temperature. Unfortunately, the second heater will not assist if the first heater fails in the reverse direction (fails to switch off). The only way to fix this is to use a decent to monitor your tank temperature and remove the defective heater. A defective heater will frequently leak electricity into the aquarium, causing major difficulties for the animals and delivering a shock to anyone who slips their finger or palm into the water (paper cuts on your hand or fingers are a great way to find stray voltage in a tank).
Something else to consider is that if you live in an area that is very cold in the winter, one heater may be stressed to keep up with low-temperature fluctuations during those long winter months.