The best aquarium heaters

Keep your fish healthy with one of the best aquarium heaters on the market.

An aquarium with seaplants, and a thermometer as well as an aquarium heater

by Isabel Martins |
Updated on

There are plenty of reasons why fish make such great pets. Apart from being super low maintenance, they along with their tanks can make beautiful and colourful additions to your home.

Whether you’re an experienced fish owner or you've just started thinking about buying some, there are a few key components when it comes to maintaining a healthy environment for your fish, one of which is an aquarium heater.

Firstly, you’ll need one that keeps a stable temperature and is very straightforward to read. You’ll also need to ensure it can be fully submerged (most can, but it’s best to always check).

We've also included the best aquarium heater for turtles, as we understand you may not specifically be looking for aquariums for fish, and what works for fish will not work for a larger animal such as a turtle.

An aquarium heater might sound expensive, but rest assured, we've included a wide range in our best aquarium heaters guide so that no matter what your budget is, you will find your ideal one.

If you do have any burning questions on this subject, make sure to read our FAQs section, where we'll discuss if you actually need an aquarium heater, plus the different types of aquarium heaters.

The best aquarium heaters

Best aquarium heater overall

This is a superb aquarium heater and an all-round excellent choice. It has several different wattage options, is fully submersible and is quite sleek so it will barely take up space in the aquarium. It features some suction cups, which allow you to place it diagonally in the water, improving its accuracy. The heater comes set at 24u00b0C, but it is adjustable between 16u00b0C and 32u00b0C. Itu2019s also shock-resistant.

Wattage options: 25w, 50w, 100w, 150w, 200w, 300w

Best for versatility
Fluval E Advanced Electronic Heater

Rrp: $64.99

Price: $43.31
Alternative retailers
Walmart$57.75View offer

As far as aquarium heaters go, this is an incredibly versatile one. It is fully submersible, and it has an alarm that changes the colour of the LED display to indicate if the temperature has increased or decreased from the original pre-set temperature. We also love that it comes with a built-in fish guard, which will ensure your fish donu2019t come into contact with the heat.

Wattage options: 50w, 100w, 200w, 300w

Best aquarium heater for smaller tanks

This aquarium heater comes with an indicator light that will let you know any changes that occur to the water temperature. Similar to the previous option, the indicator lights up when the heater is on and turns off as soon as the water reaches the pre-set temperature. Another handy feature is that has a double insulation layer, which will ensure your fish donu2019t come into contact with the heat, and has shock-resistant glass.

Wattage options: 200w

Best aquarium heater for turtles

We understand that you may not specifically be looking for the best aquarium heater for fish, so weu2019ve included the best aquarium heater for turtles, too! It is completely submersible and is automatic, the thermostat monitors the water temperature and adjusts the heater accordingly, so you will always have the ideal temperature for your turtle.

Wattage options: 50w, 75w

Best aquarium heater for larger tanks

This is an excellent choice for large aquariums as well as aquariums in general. It features a clear LED display, which shows two temperatures u2013 one being the set temperature and the other being the water temperature so you can easily compare the two. It is both shatter- and blast-proof, so as far as aquarium heaters go, it is pretty sturdy. Like many others, it has a protective heat case so that your fish wonu2019t come in contact with any heat.

Wattage options: 300w

Best value for money

Aside from having seven different watt options from which to choose, this heater will display an orange glowing light when it is on and regulating the water temperature. It additionally comes with two suction holders which will secure it in place. All in all, this is a superb aquarium heater with an incredible price tag!

Wattage options: 25w, 50w, 75w, 100w, 150w, 200w, 300w


How many watts do I need?

The wattage is what powers the heater, and on the whole, you will need about 2.5 to 5 watts per gallon of water. This is important to note, to ensure you don’t underheat or overheat the water.

What type of aquarium heaters are there?

There are four different types of aquarium heaters – immersible, submersible, substrate heaters and filter heaters.

Submersible aquarium heaters are ones that can be completely submerged in water. Immersible ones are heaters that will hang off the edge of the aquarium, whilst the heating component will sit in the water. A substrate heater works by heating up the water from the bottom up, the wires are placed on the bottom of the tank,

A filter heater, on the other hand, is more of a 2-in-1. They provide both heat and filtration for the tank. They are not the best for simply providing heat as they are more of a mixture of filters and heaters.

Do I need an aquarium heater?

This depends on the type of fish you will be keeping. If you're keeping tropical fish, you will certainly need one as fish cannot regulate their own body temperature. Coldwater fish do not require an aquarium heater.

Other animals require aquarium heaters too, such as turtles and frogs. This is due to the fact that similarly to fish, they cannot regulate their own body temperature.

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Isabel Martins is a Commercial Content Writer for What's The Best, specialising in technology.

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