Updated September 19, 2019 by Jeff Newburgh

The 10 Best Aquarium Heaters

video play icon
Best High-End
Best Mid-Range
Best Inexpensive

This wiki has been updated 13 times since it was first published in February of 2017. When it comes to taking care of your fish, environmental maintenance is one of the most important considerations. For that reason, you'll need one of these reliable aquarium heaters to help keep an eye on those piscine companions. Many function in both fresh and saltwater tanks, will shut off for safety when removed, and they'll even adjust the water temperature automatically as it fluctuates. When users buy our independently chosen editorial picks, we may earn commissions to help fund the Wiki. Skip to the best aquarium heater on Amazon.

10. Fluval E Series

9. Aqueon Pro

8. Eheim Jager

7. Finnex HMA Series

This item has been flagged for editorial review and is not available.

6. Choson Automatic

5. Ista In-Line

4. Cobalt Aquatics Neo-Therm

3. Hydor Original

2. Catalina RF-1000T

1. JBJ True Temp System

Ensuring The Longevity Of Your Aquatic Ecosystem

This heater is especially useful for those piscine aficionados interested in growing aquarium plants to create a more natural habitat for their fish.

Regardless of the species of fish you display in your home, an understanding of their biology is important. So, too, is the realization that, as cold-blooded animals, they are unable to regulate their own body temperatures the way other animals do. For that reason, you'll need a reliable heater to maintain a constant environment in your aquarium for piscine survival and longevity.

The aquarium heater is a device specifically-designed to maintain environmental stability inside a fish tank. Its core heating element is usually enveloped in either glass or ceramic, which is further contained inside a watertight plastic, glass, or steel housing fully-immersed in water. The device is also equipped with an adjustable thermostat responsible for turning the heating element on or off. Traditional aquarium heater thermostats employ bimetallic strips composed of two different metals that expand at different rates as the internal water temperature fluctuates. Other types of thermostats make use of microchips for improved maintenance and accuracy. Most freshwater and marine aquariums are maintained at temperatures between 71 and 88 degrees Fahrenheit.

Aquarium heaters are divided into four main categories, including: immersible, substrate, filter, and submersible varieties. As one of the least expensive options, the immersible heater regulates temperature by means of a control pad located above the water line. This placement makes it less efficient than other heater types, especially when it comes to heating large aquariums. It is also easy to break should it fall into the water, hence its low degree of popularity for mainstream use.

The substrate heater is not typically visible inside the aquarium and, instead, lies below the gravel normally present at the bottom of the tank. This heater is especially useful for those piscine aficionados interested in growing aquarium plants to create a more natural habitat for their fish. It also works to distribute heat evenly from the bottom of the tank. The disadvantage to substrate heaters is that everything inside the aquarium needs to be removed prior to installation.

Filter heaters minimize the amount of extra equipment needed inside the aquarium. Water is heated as it passes through the filter, making it an efficient option for use in extremely large tanks. Submersible heaters are the most popular and common of all four types, given that they waste very little energy, they can be placed anywhere inside their tanks with suction cups, and they function completely underwater.

Maintaining Balance And Knowledge

Before investing in an aquarium heater, it's important to introduce yourself to all of the requirements and processes involved in maintaining a healthy environment for your aquarium fish. Sustaining aquatic life within a controlled environment, and allowing it to flourish for an extended period of time, requires balance and patience. While it isn't always an easy job, the experience of fishkeeping is definitely a rewarding hobby.

It's also a good idea to ensure the unit has built-in overheat protection, considering that fish are quite sensitive to even minor temperature fluctuations.

Determining the type of heater that works best really depends upon the size of your tank and the types of substrate and objects you plan to place inside it. However, the majority of hobbyists tend to lean more towards the submersible variety because of its efficiency, durability, compact size, ease of installation, and its relatively inexpensive price point.

Make sure to check the rating for the heater in question to determine the size of tank it can support. Some submersible heaters are equipped with integrated memory control functionality, which is designed to maintain a preset temperature for the aquarium in the event of a power outage. It's also a good idea to ensure the unit has built-in overheat protection, considering that fish are quite sensitive to even minor temperature fluctuations. If you do need to adjust the temperature of your aquarium, it's not difficult to find an option with a dedicated control knob for manual adjustments. Depending on the size, shape, and nature of your tank, consider a heater that installs vertically or horizontally and is capable of working in both salt and freshwater environments.

A Brief History Of The Aquarium Heater

Archaeological evidence suggests that fishkeeping dates back to the times of the ancient Sumerians and Egyptians between 5500 and 2500 BCE. For example, the ancient Egyptians considered the fish sacred, even going so far as to worship the Nile Perch among other species. The Roman Empire also maintained rudimentary aquariums for the purpose of piscine consumption.

Records from the Chinese Sung Dynasty suggest that people selectively kept and bred carp for ornamental purposes between 960 and 1279 CE.

Jager's design was later marketed in the United States during the 1970s.

The first practical use of the aquarium heater occurred during the Victorian era in Europe. With the opening of the first public aquarium at the London Zoo in 1853, there was a cultural renaissance of sorts during which people became fascinated with the study of animals and nature. Flames from oil lamps were used to heat fish tanks from below using slate bottoms. With the introduction of electricity into the home, people began to experiment with immersion heaters in glass tubes.

By the 1920s, the first tropical fish were being sold in toy stores. After World War Two, fishkeeping became more of a mainstream hobby accessible to the middle class, thanks to advances in aviation that made it possible to transport a more diverse population of fish species all over the world.

The first reliable submersible electrical heater was invented by Eugen Jager in the 1960s. Jager's innovative design served to eliminate the dangers associated with older, over-the-side type heaters with the use of a borosilicate tube and an integrated bimetallic thermostat. Jager's design was later marketed in the United States during the 1970s. Since that time, the device has become an integral part of the hobbyist's aquarium setup.

Statistics and Editorial Log

Paid Placements
Rendering Hours

Granular Revision Frequency

Jeff Newburgh
Last updated on September 19, 2019 by Jeff Newburgh

Jeff is a dedicated writer and communications professional from San Francisco with a bachelor of arts in anthropology from UC Berkeley. He began his career in computer consulting and later branched out into customer service. Jeff focuses on making complex topics easy to understand. With over 10 years' experience in research, his relentless curiosity fuels a love of writing and learning how things work, and has helped to build expertise in categories such as heavy-duty power tools and computer equipment. Jeff's passion for animals affords him a strong understanding of pet products, including dog houses, beds, and grain-free foods. When he's not writing, he prefers spending time with his family and three dogs, while kicking back and relaxing with a nice glass of red wine.

Thanks for reading the fine print. About the Wiki: We don't accept sponsorships, free goods, samples, promotional products, or other benefits from any of the product brands featured on this page, except in cases where those brands are manufactured by the retailer to which we are linking. For more information on our rankings, please read about us, linked below. The Wiki is a participant in associate programs from Amazon, Walmart, Ebay, Target, and others, and may earn advertising fees when you use our links to these websites. These fees will not increase your purchase price, which will be the same as any direct visitor to the merchant’s website. If you believe that your product should be included in this review, you may contact us, but we cannot guarantee a response, even if you send us flowers.