Aquarium heating guide


Heating your tank can be the difference between keeping cold water fish, or being able to keep tropical fish. All fish species require different temperature ranges, according to where they originate from in the wild.

Using a simple heater

A simple heater is used to accommodate any fish, as they usually range from 18-34c (64-94f). Aquarium heaters are automatic and don’t need any maintenance. Almost everybody in the aquarium hobby will be using a submersible heater. the only thing you need to do with your heater is to set the initial temperature you want the tank water to be. Heaters will turn themselves on/off when they need to, hence no manual adjustment needed. These heaters keep a very stable water temperature, which is what your fish need.

Heaters can fail over time, or even more worrying can ‘stick’ to a permanent ‘on’ position. This is why it’s important to keep an eye on your temperature reading, and to keep a spare heater as a backup.

Temperature reading

Aquarium glass thermometers attached via a sucker, on the inside of your tank is all you need to get accurate temperature reading. For better accuracy the thermometer needs to be situated at the opposite end to the heater. Be careful as almost all heaters are off by a certain degree, giving you a slightly false reading. This can vary, judging by how powerful the heater is, to how much water its heating. Once you have the heater set, keep an eye on your thermometer to see the true temperature it’s heating the water up to. The heater can then be adjusted accordingly.