Best aquarium heater 2017

Best aquarium heater 2017 DEFAULT

The 10 Best Aquarium Heaters

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This wiki has been updated 19 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 your aquatic companions comfortable. Many function in both fresh and saltwater tanks, will shut off for safety when removed, and will even adjust the water temperature automatically as it fluctuates. When users buy our independently chosen editorial selections, we may earn commissions to help fund the Wiki.

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This wiki has been updated 19 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 your aquatic companions comfortable. Many function in both fresh and saltwater tanks, will shut off for safety when removed, and will 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.

Editor's Notes

February 15, 2021:

It wound up being quite a busy round of updates, as many of our previous selections seemed to be no longer available, and therefore needed replacing. The options we removed were the Catalina RF-1000T, Tetra HT, Fluval E Series and Cobalt Aquatics Neo-Therm.

Some of the new choices we added include the Aqqa Fish Tank Heater — an 800-watt model that can handle aquariums as large as 220 gallons, and sports a smart color LED display; the Orlushy Marine — which inconveniences users with its submersible, analog controls, but redeems itself slightly with the inclusion of an external aquarium thermometer; and the Hygger HG-802 — which features an IPX8 element, external controls and a wide temperature-control range of 32 to 104 Fahrenheit.

One thing that surprised us during our research is how behind the times this niche category is in terms of offering models that hook up to Wi-Fi. While it’s certainly true that hobbyists got by for years without it, remote monitoring would still be a nice touch, given how pricey some of these setups are (not to mention that your pets live inside them). If you’re trying to figure out the easiest way to set yourself up with some remote monitoring/control options, the simplest solution might be to hook an element up to a line-voltage temperature controller with Wi-Fi connectivity.

While you're here, you may also be interested in checking out a few more of our aquarium-related rankings. We've got lists for air pumps, skimmers, stands and more.

October 14, 2019:

Whether you’ve got a three-gallon fish tank or one with a capacity of 90 gallons, a reliable aquarium heater will maintain the water’s temperature properly to keep your fish free of the stress associated with frequent temperature changes.

Coming on board today is the Finnex Digital, which is built with safety in mind, with an alarm that will sound if your tank’s water becomes too hot or cold. This powerful choice is suitable for use indoors in your aquarium or outdoors in a backyard pond or a greenhouse. It features a large panel with a user-friendly interface and will retain its settings in the event of a power loss.

Also joining the list is the Hygger Submersible which comes in your choice of 50, 100, or 300 watts, depending on your tank size. It too has several safety features, such as overheat protection and an automatic shutoff if an electrical fault occurs. It can be placed unobtrusively behind plants or rocks, thanks to its small footprint. It’ll maintain your tank’s water in the constant temperature you set, and will reliably stop heating when your water’s temperature is 1.5 to 2 degrees Fahrenheit above or below the set temperature.

Another new addition is the Tetra HD, which comes from a popular name in fish care. This 50-watt, budget-friendly choice is simple to set up and maintain, with a red light indicating it’s heating the water and a green one to let you know it’s on standby. Unlike many others, you can position it either vertically or horizontally, and like the Hygger we added, this one is also easy to hide behind plants, rocks, or other tank décor.

Leaving the selection in today’s update is the JBJ True Temp System, amidst reports the heating element can malfunction and create undesirable temperatures in the tank. The Finnex HMA Series and the Choson Automatic also make departures, due to availability issues.

Special Honors

Aquarium Guardian This nifty unit can monitor the temperature and water level in both freshwater and saltwater tanks, and keeps their owners notified of both via text message, so there's no need to download another app. It isn't a one-stop solution for those looking to fully automate their setups, but it does come with an integrated relay that can either be used to control a heater, lights, or even a pump or solenoid valve to top the tank off when your water level gets low.

Inkbird C929A The C929A is a digital temperature controller that issues user notifications via Wi-Fi anytime it runs into any trouble. It uses a dual probe to help ensure good accuracy, and while it doesn't come with a heating element, it does provide an AC outlet capable of feeding up to 1,200 watts of equipment — which means you might be able to get away with using this one to control an old heater with an internal thermostat that's starting to give out.

Ensuring The Longevity Of Your Aquatic Ecosystem

The disadvantage to substrate heaters is that everything inside the aquarium needs to be removed prior to installation.

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.

Since that time, the device has become an integral part of the hobbyist's aquarium setup.

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.

Will Rhoda
Last updated on February 17, 2021 by Will Rhoda

After deciding that the pen was mightier than the pliers, Canadian electrical contractor William Rhoda abandoned his career and headed back to college, where he majored in marketing and advertising and won a scholarship along the way to earning a diploma in creative communications. His past career landed him a depth of knowledge in tools and hardware, while his current career schooled him in audio, video and camera equipment. During his leisure time, he’s learned lots about outdoor gear, and years of tiresome backyard maintenance have taught him all about pools and hot tubs. His recreational pursuits include rest, relaxation and revolutionary action, and his roommate’s a hairless cat.

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July 27, 2021

Watching fish swim, glug, and blub all day can bring hours of enjoyment. To keep your fish happy and healthy, they need an adequate home—and a decorative jar with a few rocks ain’t going to cut it. After interviewing two aquarists and one aquaculturist, and researching dozens of aquarium goods, we recommend the 20-gallon Marina 20G LED Aquarium Kit as a great freshwater starter tank because it’s the most versatile kit we found.

Even though it lacks a heater, the Marina 20G LED Aquarium Kit is hands down the most impressive tank kit we tested. Of all the kits we considered, the Marina has the brightest light and the most elegant design, and it has a stable, customizable filter that will keep beneficial bacterial colonies alive much better than any other kit filter. The Marina kit’s only drawback is its omission of a heater, but no kit comes with absolutely everything you need to get started, and if you add our heater pick, for only a little more money you end up with a substantially better setup than other kits we tested.

If you buy the Marina kit for use with tropical fish, you'll need a heater. The 100-watt Eheim Jäger Thermostatic Aquarium Heater is the best we found for a 20-gallon tropical tank after researching more than a dozen and testing seven. It has the largest temperature range of any heater we tested—from 65 to 93 degrees Fahrenheit, in two-degree increments—and its temperature-control ring is easy to see and adjust without putting your hands in the tank.

If our main pick sells out, or if you want a kit that includes a heater, the 20-gallon Aqueon LED 20 Aquarium Kit is a good alternative. Compared with the Marina kit, it has a dimmer light and a less powerful filter, though both are still decent. Its preset heater isn't as good as our adjustable stand-alone recommendation, either. But it’s available at a great price for a kit that contains all the basics for a tropical tank, from a company with reliable customer service and a huge range of compatible accessories that are available at most fish shops. It's the second-best tank kit we found after the Marina offering.

An aquarium kit comes with a tank, a light, a filter, and (usually) a heater. But you'll also need substrate, water conditioner, a water test kit, a gravel vacuum, food, an algae sponge, and fish. We have recommendations for all of those components (except the fish), and you can buy most of them online, though you should plan a trip to your friendly local fish store for the fish and for advice on the best way to set up your tank.

While either the Marina or Aqueon starter kit will give you a good basic setup for a great price, you can get significantly better equipment by buying components individually, which will likely improve the conditions for your fish. Buying our individual picks for tanks, filters, heaters, and lights will cost between $30 and $70 more than going with a kit, but you'll end up with a more powerful and versatile filter, an adjustable heater, and a significantly brighter, customizable light, which is important if you plan to grow live plants.

Why you should trust us

To get a better sense of the best equipment and practices for beginning and intermediate freshwater-aquarium owners, I spoke with several experts for guidance. Chi Cho, the co-owner of Pacific Aquarium in New York, took me around his store and explained what equipment he used with each of his tank setups. I also interviewed Keith Seyffarth, the creator of the site The First Tank Guide. Seyffarth, who used to manage the fish department in his local pet store, has kept fish for over 35 years in tanks as small as 2.5 gallons and as large as 180 gallons. And I spoke with Jesse Trushenski, fish pathologist supervisor at the Idaho Department of Fish and Game, about what your fish needs to stay healthy. I also read dozens of fish-tank enthusiast blogs, dove into aquarium forums, sorted through hundreds of owner reviews, and played phone tag with many customer service representatives.

I got my first aquarium, a 30-gallon tropical setup, when I was in third grade. Since then, I’ve had three other freshwater tanks, some planted and some not, that I’ve sustained with the help of four local fish shops in three states. I also gave a TEDx Talk about proper aquarium care and wrote my college admissions essay about a fish born in my tank. I currently have a resilient veiltail betta, Ralph, who I’m planning to rehome in one of our picks.

What you need to know before starting an aquarium

A blue and red beta in its tank.

People have kept fish in tanks for roughly 4,500 years, and the tools and techniques of the trade have improved exponentially since then. If you’re serious about starting a home aquarium, you’ll need a fish tank, a filter, a heater, a light, a lid, substrate, water conditioner, a water test kit, a gravel vacuum, food, and an algae sponge.

But before you buy your equipment, think about what fish you’d like to keep. Thousands of fish are suitable for aquarium life, and the type of fish you want will inform what kind of equipment you need. You’ll find tropical and temperate fish, freshwater and brackish-water fish, big and small fish, and peaceful and aggressive fish. Some schooling fish like to live in groups, and others, like bettas, need to be alone. We recommend doing some research to see what kinds of fish are out there and whether they’re compatible.

While you can buy all the right equipment online, you can’t Amazon Prime your fish. We recommend going to a local fish store (Yelp is probably your best bet to find one) as opposed to a pet superchain like PetSmart or Petco, whose aquarium sections often contain diseased fish and apocalyptic tanks where fish eat their deceased brethren. Local fish stores (abbreviated online as LFS) will generally have healthier animals and a wider variety of higher-quality equipment. These shops are generally run by people passionate about fish, so they’ll be better able to answer your questions about your own aquarium and how best to fill it.

But when you’re in any fish store, whether chain or mom-and-pop, be sure to check the quality of the wares. See if the tanks are noticeably dirty, or if they contain many dead fish. If their bettas are in blue, medicated water, that’s a good sign. If they sell dye-injected fish, that’s a bad sign (but the genetically modified GloFish, which contain genes from naturally bioluminescent animals like sea anemones, are healthy and harmless).

Local fish stores (abbreviated online as LFS) will generally have healthier animals and a wider variety of higher-quality equipment.

Once you’ve bought a tank and all the other equipment you need, there’s one final step. An aquarium, unlike nature, is a closed system. So when fish poop and leave behind uneaten food, that waste stays inside the tank. This decaying organic matter releases ammonia into your tank, and it’s up to the colonies of beneficial bacteria that live in your filter to break down the ammonia into nitrite, turn nitrite into nitrate, and then remove the nitrate altogether (this process is called the nitrogen cycle.) New aquariums don’t come with this bacteria, so you’ll need to cycle your tank, a process of establishing and maturing colonies of beneficial bacteria in a filter.

You have two different ways to cycle your aquarium. In the first method, you use two or three hearty fish and allow bacteria to multiply to handle their waste. It’ll take around eight weeks and require frequent water changes to ensure your fish don’t die, but this way you can add those two or three fish immediately. In the second method, also known as fishless cycling, you add a small dose of concentrated ammonia once the tank is set up but before the fish are in, and let the tank take care of the rest. You can buy a bacteria starter to speed up the process, but your local tap water already contains some of that needed bacteria, which will multiply around an ammonia source. It doesn’t take as long as cycling with fish, but it can be frustrating to buy everything you need for a tank and then leave it empty for over a month. We like this guide on cycling with fish and this guide on fishless cycling. But whichever method you choose will set your tank up for success and ensure that your fish don’t kill themselves with their pee.

These precautions may seem overwhelming, but they’ll pay off in the long run in the health of your fish and the amount of regular care they’ll need. And after you’ve had your aquarium for a few months, we promise it’ll be second nature.

How we picked and tested

A number of twenty gallon tanks set up in a room for testing.
A person using a colander to add dechlorinated water to a fish tank.

We called in samples of our top tank kits, stand-alone tanks, lights, heaters, and gravel vacuums to test in person. We based our recommendations for algae scraper, water conditioner, gravel and soil substrates, and fish food on research, but we called in samples of our top choices to make sure they worked. (They did.)

For someone who has never owned an aquarium before or doesn’t have too much experience in the hobby, our experts recommended starting with a 20-gallon tank or larger because it’s harder to mismanage and better able to rebound from chemical spikes. Although this may seem counterintuitive, small fish tanks are much harder to keep than large fish tanks. A small ammonia spike can be tolerably diluted in a 30-gallon tank but lethal in a 10-gallon one. The smaller the tank, the smaller the margin for error. If 20 gallons sounds big to you, we promise: It’s not as big or daunting as it sounds.

Our experts recommended starting with a 20-gallon tank or larger because it’s harder to mismanage and better able to rebound from chemical spikes.

Tanks generally come in two materials: glass and acrylic. After researching both, we think glass is the better tank material for any aquarium under 75 gallons. Glass tanks cost a third or a quarter as much as acrylic tanks, plus they scratch far less easily and won’t yellow or fog with age. Acrylic tanks are shatterproof, which makes them a better pick for huge, public aquariums. They’re also lighter, but that doesn’t matter much since you’ll be filling the tank with hundreds of gallons of water anyway. “I always recommend glass over acrylic, unless you go over 300 gallons. Then people get more curious, they see big beautiful fish and want to tap on the glass,” Pacific Aquarium’s Chi Cho said.

No aquarium can clean itself, so you’ll need a strong filter to remove the rotting food, sunken fish poo, and other decaying organic material that naturally accumulates in a thriving fish tank. You’ll encounter three types of filtration—biological, mechanical, and chemical—and all three are important, so we looked for filters that offered the option to do all three, all while processing the entire volume of a tank twice in an hour. While many different types of filters exist, we looked only at power filters, which hang on the back wall of the aquarium and use an electrical pump to move water through the filter media. This type is the most common filter for freshwater tanks, and also the kind our experts recommended. In addition, we calculated the maintenance costs of all the leading aquarium filters (how much the replacement cartridges and sponges cost, and how often you need to replace them), as the best filters should be affordable to maintain.

No aquarium can clean itself, so you’ll need a strong filter to remove the rotting food, sunken fish poo, and other decaying organic material that naturally accumulates in a thriving fish tank.

If you plan on having tropical fish, you’ll need a heater to keep your fish healthy and happy. After researching several types of heaters, including those that can hang from the side of a tank, slip underneath gravel, or sit inside a filter, we focused on submersible heaters that attach to tank walls with suction cups because they’re the most efficient and easy to use. We considered only those heaters that had adjustable dials for setting the temperature, ideally offering precision of one Fahrenheit degree or better.

Six water heaters draped on the side of a fish tank.

Some fish, such as the Celebes halfbeak, have a very narrow window of appropriate temperatures, so a good heater should keep the actual water temperature within ±1 °F of the temperature indicated on the heater’s dial or internal thermometer. But even if you have fish that can survive in a wider range of temperatures—the popular dwarf gourami can thrive anywhere from 72 to 82 °F—all fish are sensitive to temperature changes. Fluctuating water temperature can affect their immune system and lead to outbreaks of ich, a parasitic aquarium disease that causes small white spots to appear on your fish and can be lethal if untreated.

While a cheap dog bed may be less comfortable for your dog, a cheap filter could fail and kill your fish.

If you decide on keeping goldfish or other temperate fish, there’s good news: You don’t have to buy a heater. But be sure to research which kinds of fish you want in your aquarium, as you can’t keep temperate fish with tropical fish.

While you may be able to find cheap, passable filters and heaters from well-known aquarium brands like Aqueon and Tetra, trust us when we say it’s worthwhile to spend more than the bare minimum to invest in quality equipment for your fish. While a cheap dog bed may be less comfortable for your dog, a cheap filter could fail and kill your fish. And fish are expensive pets only when you’re starting out. After you buy your initial setup, maintenance will rarely cost more than a few dollars a month, and you’ll never have to splurge on insurance or regular vet visits, which furry pets require.

The lights shown are not the brightest, but they're brighter than most and seem the most even in terms of illumination.

Aquarium lights come in a variety of bulb types, including fluorescent, incandescent, and, more recently, LED. We found LED lights to be the brightest and most energy-efficient kind. And because they seem to last forever, they’re the most affordable over the long term. Incandescent bulbs need replacing often and run hot, possibly changing the temperature of your tank. And fluorescent bulbs, while cooler and longer-lasting than incandescent, still don’t measure up to LED strips in energy efficiency. We also researched the different light settings you’ll need for a regular and planted aquarium, and we have recommendations for both. To test the brightness of the LEDs, we took high-resolution photos of the lights turned on above a tank in a pitch-black laundry room.

All starter aquariums include some type of lid, which will keep evaporation low and your fish from leaping to an untimely doom. Some fancier, rimless tanks forgo tops for a more elegant look. Just be careful to avoid buying fish that are known jumpers, and think twice if you have cats in your home.

We found too many miniature castles, treasure chests, and fake plants for us to recommend any one in particular, but we can offer some general guidelines for decorating your aquarium. Choose only those items that are advertised as aquarium-safe, meaning that they’re sold in a fish store or within the aquarium section of a pet store or online retailer. Most non-specialized figurines include paint or chemicals that can be toxic to your fish. Case in point: One Halloween, my dad surprised me by decorating my tank with spooky skulls and spiders he bought at Walgreens. It gave me a real scare when I woke up the next morning to a tank of dead fish.

If you do choose to plant your tank, consider which type of fish you'll be keeping in it. For example, fish that live in ponds love soft and lush plant cover, whereas fish that live in faster waters prefer logs and rocks. This is a good introductory guide for anyone looking to start planting.

You may have also read that your aquarium should rest on a stand. While you don’t need to buy a custom-fitted cabinet made of cherrywood, you can find many sturdy metal stands that cost as little as $60 and can safely support your 20-gallon tank. (If you have another size tank, check out this helpful gallons-to-weight chart.) If you don’t want to buy a dedicated stand, just make sure to put your aquarium on something wide and sturdy that can comfortably hold all 225 pounds of your filled 20-gallon tank—so no repurposing your IKEA Lack or Hemnes.

Tank kit

The marina 20g led aquarium kit set up on a wooden dresser.

After researching 10 glass 20-gallon aquarium kits and testing five, we concluded that the Marina 20G LED Aquarium Kit is the best kit for most people looking to start an aquarium. The Marina kit has the most powerful filter and the brightest built-in light of all the kits we tested, and its sleek lid makes it look much more elegant than many tanks that cost more. The Marina kit includes a hanging power filter, an LED hood with a light switch, a few sample packets of fish food, starter bacteria, and water conditioner, as well as a net. Unlike all the other kits we considered, the Marina kit doesn’t include a heater, which is a vital piece of equipment for most tropical setups. But we didn’t love the heaters included in any tank kit. Buying the Marina kit plus our heater pick will cost a bit more than buying our runner-up, the Aqueon kit, which includes a preset heater, but our heater pick will support a wider range of tank temperatures. The Marina offering contains the highest-quality component parts of any kit—and we’d rather have a kit with an excellent filter and no heater than a kit with a decent filter and a heater with only one temperature option—so we still think the Marina kit is a better buy.

The individual cartridges for the marina filter shown without water present.

What sets the Marina kit apart from the others is its large, customizable power filter, which can nurture beneficial colonies of bacteria better than the other, flimsier filters included in tank kits. This filter is a long, slim, and empty bucket that you can fill with up to four of Marina’s ready-made cartridges. In contrast to what’s in all the other tank kits we tested, these Marina cartridges include porous ceramic pebbles and have more surface area than other types of filters, which means more space for the beneficial colonies of bacteria that live in the filter and detoxify fish waste. And the filter’s four-cartridge system means you can replace cartridges one at a time, effectively preserving the majority of your bacteria colonies. With other, single-cartridge filter systems, such as those of Aqueon, Tetra, or Marineland, you lose all your bacterial colonies during routine replacements of the filtration media, which ends up cycling your tank again and causes undue stress to your fish.

We also like that Marina offers two types of filter cartridges, one meant for tropical fish and one meant for goldfish, which pee a lot more than other fish and therefore require more ammonia-fighting filter media. And if you want even stronger filtration—which is never a bad idea, especially for well-stocked tanks—you can fill the bucket with the filter media of your choosing. If that interests you, we like this impressively thorough guide.

This looks like the tank light photo from above, with distinct blue-white bands.

Evaluating the LED lights of the Marina kit. Photo: Sabrina Imbler

These lights are very similar in appearance to the Marina; perhaps slightly less bright.

The Aqueon kit. Photo: Sabrina Imbler

This light kit has a similar pattern of illumination to the first two, but is noticeable dimmer.

The Marineland kit. Photo: Sabrina Imbler

This lighting kit is the dimmest thus far; it's hard to make out its illumination pattern except at the top of the tank.

The Elive kit. Photo: Sabrina Imbler

This kit appears fairly bright, comparable to the first two.

The Tetra kit. Photo: Sabrina Imbler

The Marina kit’s built-in LED strip was the brightest of any we tested, illuminating every corner of the tank with an even, white glow. Instead of offering a long, continuous strip like the Marina kit, the Aqueon and Tetra kits included four or five separate LED lights, which lit the tank in uneven spotlights. The Marineland kit’s shorter, chunkier light was far too dim, and the Elive kit’s short, hemi-donut light illuminated only the center of the tank and barely reached the bottom.

This image displays the four light kits listed top-up on the floor. They're all black plastic rectangles except the Elive, which is a small plastic semicircle; the Marineland appears thicker and more rounded.

Clockwise from top left: Tetra, Aqueon, Marina, Elive, Marineland. Photo: Michael Hession

The same five light kits from the bottom this time, to show their LEDs. Most have some arrangement of an LED grid, while the Marina appears to have a single, large light bar.

Clockwise from top left: Tetra, Aqueon, Marina, Elive, Marineland. Photo: Michael Hession

Components aside, the Marina tank is a cleaner-looking, more attractive model than the others we tested. Its black plastic lid slopes up toward the back in one piece, with one wide gap and one narrow gap in the back to accommodate a filter and a heater and one small gap in a front corner that lets you feed your fish without lifting the lid. The tops on the Aqueon and Tetra tanks looked much bulkier, featuring recessed lines with no apparent purpose etched along the plastic lid. We liked the sleek appearance of the Elive kit’s single-panel glass lid but found it stressful to remove, as we didn’t want to put a pane of glass on a hard floor but also didn’t want to get any aquarium water on a rug.

Flaws but not dealbreakers

The Marina kit's box pictured with a net and bottles of food and other supplies; the box says "power filter."

Note that the Marina kit lacks a heater. A tank kit that’s missing such a vital piece of equipment may not seem like much of a kit in the first place. But no kit in our test group includes everything you’ll need to start an aquarium, such as a year’s supply of food and water conditioner, a gravel vacuum, or even fish. Since you’ll be buying those supplemental pieces of equipment anyway, we think it’s not a big deal to add a heater (such as our pick, the 100-watt Eheim Jäger) to the mix, as it will also be a much higher-quality, adjustable heater than the one found in other kits, and it’ll make keeping your fish healthy easier. Also, the preset heaters found in most kits can sometimes be calibrated wrong, and without the ability to adjust the temperature manually, that could be fatal to your pets. There are certain things you just can’t upgrade in a starter tank, such as the light (which is generally attached to the lid) or the tank itself. So we think buying a tank with the highest possible quality of those irreplaceable parts is the best choice, and that choice is the Marina kit.

No kit in our test group includes everything you’ll need to start an aquarium, such as a year’s supply of food and water conditioner, a gravel vacuum, or even fish.

A runner-up kit with a heater

The Aqueon tank, empty on a dresser.

If the Marina kit sells out, or if you don’t want to buy a separate heater, we also like the Aqueon LED 20 Aquarium Kit. It’s a more complete kit than the Marina offering, and Aqueon items are sold in virtually every aquarium store, local or chain, so you’ll never have to worry about finding replacement parts. The Aqueon kit also comes with a heater, which the Marina kit lacks, though it's preset to 78 °F—a good baseline for many tropical fish, but you can’t adjust it to account for the temperature of your room or the needs of more fastidious fish (though you can always replace it with our heater pick later). The Aqueon lid also looks clunkier and less sleek than the Marina lid, and its lights are dimmer and less even. Unlike Marina’s filter, Aqueon’s filter is a single-cartridge design, which does not allow you to swap out filter refills without cycling the tank water. But Aqueon’s filter comes with a lifetime warranty, which far surpasses the Marina filter’s two-year guarantee (PDF), and the kit itself is still the second-best of any we tested.

The Aqueon kit looks almost identical to the kit I tested from Tetra, in appearance, light, and add-ons—I had to label them so as to not mix them up during testing—but it distinguishes itself with a slightly better filter (though one that’s still notably inferior to the Marina filter). Both the Tetra and Aqueon filters use a cartridge containing activated carbon and dual-sided mesh, but the Aqueon model also includes a slot for an extra filter pad meant to remove ammonia. We also preferred Aqueon’s instruction packets, which cogently explain how the filter works and how to assemble it. Tetra’s manual is much more sparse and refers to the cartridge only as a Bio-Bag, which feels condescending to people who want real information. But the Aqueon filter is not too powerful, so you should be careful not to overstock the tank with too many fish (the general rule is 1 inch of fish per gallon of water—so you can have no more than 10 2-inch-long fish in a 20-gallon tank).

Pictured: supplies including a filter, net, and water conditioner.


The Eheim heater, which has a large top dial with extensive labeling.

After researching more than a dozen heaters and putting seven through a battery of tests, we found that the 100-watt Eheim Jäger Thermostatic Aquarium Heater is the best heater for 20-gallon tropical tanks. It can calibrate heat to half a degree, and with a dial that you can adjust anywhere from 65 to 93 °F in two-degree increments, it boasts the largest temperature range of any heater we tested. (In our interviews, however, Pacific Aquarium’s Chi Cho and The First Tank Guide’s Keith Seyffarth agreed that it’s best not to trust such numbers at face value; both recommended buying a separate thermometer to read the temperature of the tank.)

To test the heaters, we timed seven different 100-watt models on how long each took to heat a tank full of 20 gallons of 70 °F water (around tap-water temperature) to 79 °F (a good temperature for tropical fish). All of the models heated the tank in around four and a half hours and were able to maintain a temperature of 79 °F, give or take a degree, over the course of five hours. When each tank was fully heated according to our separate thermometer, we checked if the heating indicator light had turned off, and then removed each heater to see if it would automatically shut off when not in water. Most of the heaters passed our tests, and from there we made our choice based on precision, range, and appearance. While Cho said he had no brand preference in heaters, Seyffarth told us he used the Eheim Jäger on one of his tanks.

A closeup on the Eheim heater's dial; its numbers start around 65 and go up to the mid-80s.

The Eheim Jäger features a blue temperature selector ring at the top of the heater, where it’s easy to read and adjust from above. We prefer being able to adjust the heater manually while seeing the temperature selector change from the same perspective. With other heaters, we could see the internal thermometer only head-on and turn the dial only from above, which felt uncomfortable and required checking back and forth. And if you fill your aquarium with plants and decorations, it’ll be a nuisance to have to push them aside to read the temperature on your heater. The Eheim Jäger’s dial is considerably stiffer than the dial on the Aqueon or Marina heater. But we actually found this to be a blessing, since more-lubricated dials can turn easily with an accidental bump or graze while you’re cleaning, raising the potential for disaster. And after you turn a heater’s temperature dial once, you probably won’t need to turn it again.

At 12.6 inches, the Eheim Jäger is longer than the other heaters we tested, but its solid black color and glass body are unassuming and easily hidden behind plants. Its cord is thicker and harder to coil than most others but still long enough to reach an outlet up to 6 feet away.

The Aqueon heater appearst o be a single piece of hard plastic, save for the dial itself.

The 100-watt Aqueon Pro Heater is a great alternative if you want a solid warranty and can live with significantly less precision. Unlike glass-based heaters like the Eheim Jäger or the Marina, which can sometimes trap condensation inside, the Aqueon Pro Heater’s shatterproof aluminum core is close to indestructible. Its sleek, matte-black design is easily obscured by a plant or two. And while the Eheim Jäger heater has a three-year warranty and the Marina heater has a two-year warranty, the Aqueon model is guaranteed to work for life. Owners report great experiences with customer service when ordering a new heater under the lifetime warranty. But this Aqueon model’s temperature dial is marked in intervals of four degrees (for instance, 72, 76, and 80 are in sequence), which makes it hard to know where the thick blue dial is pointing—and by extension, what temperature your tank is.

Any preset heater, such as this best-selling Tetra model on Amazon, or many of the heaters included in tank kits, will work in a pinch, but we do not recommend buying one on its own. A good heater should be adjustable because not all fish require the same temperature, and preset heaters can be calibrated wrong, sometimes to the tune of several degrees.


The Current USA light, a slim bar that fits laterally over the top of the tank.

After researching nearly a dozen aquarium lights and testing five, we think the Current USA Satellite Freshwater LED is the best light for most aquariums. At just 2 inches wide and less than half an inch tall, it’s the slimmest, sleekest light of the bunch, but it still illuminates the corner of a tank more evenly than lights twice its size. The Current USA model also features seven customizable blue and white light settings and dimmable control to suit your preference. If you have a 20-gallon tank, we recommend the 24-to-36-inch model, which features 66 white LEDs (6,500 K) and 36 blue LEDs (445 nm).

To test the lights, we placed each model over a filled 20-gallon aquarium in a pitch-black laundry room and took photos of the light they cast using identical settings on a digital camera. These pictures displayed striking differences between lights that looked pretty similar during the day—which shouldn’t matter much to you or your fish, but could make a big difference in the health of your plants.

The lights shown are not the brightest, but they're brighter than most and seem the most even in terms of illumination.

The Current USA lights were slim, sleek, and bright. Photo: Sabrina Imbler

The Finnex lights are by far the brightest so far, casting a shadow from inside the tank.

If you want extra illumination for plants, Finnex’s Planted+ gives you more options and more lumens. Photo: Sabrina Imbler

The Nicrew lights are almost as bright as the Finnex's, with a slightly more purple hue.

Nicrew’s LEDs are good and cheap—but they come from a company without much of a reputation. Photo: Sabrina Imbler

The Current USA model provided even, uninterrupted light to all corners of the tank. The chunkier Marineland and shorter Aqueon light fixtures both produced a harsh spotlight in the center while leaving the corners dark. The short docking legs of the Current USA light make it lower profile than other models, allowing the upper rim of the tank to obscure the direct light of the LED strip. The result: a tank with the pleasant appearance of a softly glowing box. The tall legs of the cheaper Nicrew and pricier Finnex lights we tested both stood an inch or two above the rim, which left the bright circles of the strip visible from a head-on view.

While your fish won’t care about customizable settings that mimic light from lightning storms and cloudy days, we think they’re super cool. The Current USA light includes a remote control with seven preset lighting modes that mimic dusk, a sunny day, and the blue light of the moon, each of which you can further customize by dimming.

The small remote pictured has buttons that say "+ / -", "Blue", "mode" and "white."

The Current USA model was not the brightest light of the bunch, so if you want a planted tank, you may be better off with the Finnex light (it won’t affect the fish one way or the other). But the Current USA light’s slender size and customizable glow make it the perfect light for most tanks, and it’s still bright enough to support plants that require low to moderate light.

The Nicrew pictured from above, showing its notably larger size.

If the Current USA light sells out, or if you don’t care about customizable settings, we recommend the super-bright and super-affordable Nicrew White and Blue LED Aquarium Light. It’s less than half the price of the Current USA model, and in our tests it gave off the second-brightest light. We also liked its sturdy docking legs, which felt less shakeable than the Current USA and Marineland models’ simpler legs. The Nicrew light offers two lighting modes, a white and blue daylight setting and a blue-only nighttime setting. These lights are so bright that we wish this model came with a dimmer; still, too-bright lights aren’t the worst problem to have. Nicrew is also a fairly new company on the scene and its items are currently available only through Amazon, so you probably won't find them at your LFS.

The Finnex from above--it's slim and low-profile.

If you love the thought of an underwater jungle and want to have a planted tank, the Finnex Planted+ 24/7 Automated LED is vivid, versatile, and by far the best light we tested. With RGB and 7,000 K daylight LEDs, it gave off the brightest light in our tests by a wide margin. And the Finnex model’s light was an unpolluted white, unlike the blue-tinted glow from the Nicrew—a purely aesthetic difference, but a nice one. This model, however, is around twice the price of the Current USA light at this writing, and its brighter lights and advanced settings are human-oriented luxuries that won’t make a difference to your fish, so we recommend the Finnex only if you’re serious about plants.

The Finnex' multi-button remote has controls for color temperature, timing, and demos.

Like the Current USA model, the Finnex light fixture contains special lighting modes that mimic thunderstorms, cloudy days, and moonlight. But Finnex’s remote-controlled customization goes one step further, allowing you to change the colors of your tank to any dimmable combination of red, green, and blue. The remote also contains built-in memory that can save custom color schemes and retain a set lighting cycle where your tank lights gently dim on and off on a schedule of your choosing.


The Aquaclear filter hooked to the edge of a tank; it's a few inches wide and has a series of small tubes coming out of its boxy plastic body.

After researching dozens of filters of six different types and narrowing the list down to eight finalists, we think the AquaClear Power Filter is a superior, versatile filter that’s easy to maintain. According to Pacific Aquarium’s Chi Cho, “AquaClear is the number one filter. It sets itself above and beyond all others.”

The porous ceramic rings make the AquaClear filter the gold standard for freshwater filters; no other filtration medium has as much surface area to allow large colonies of bacteria to thrive.

The AquaClear model filters water in three stages: mechanical, biological, and chemical. And it’s important that a good filter do all three. At the bottom of the filter’s bucket, a porous foam block provides mechanical filtration by trapping any large debris or particles that enter the filter. Above the foam, an activated-carbon filter keeps the water in your tank clear by adsorption, or chemically binding toxins to its surface. Finally, on top, a bag of ceramic rings creates a porous system that provides the perfect home for colonies of beneficial bacteria that process the toxic waste in your tank into less harmful substances.

A side view of the filter's interior: foam forms the base, a small bag of carbon sits on top, and a bag of rock-like ceramic rings sits on top.

The porous ceramic rings make the AquaClear filter the gold standard for freshwater filters; no other filtration medium has as much surface area to allow large colonies of bacteria to thrive. None of the other filters we researched offered such effective filtration media: The Aqueon QuietFlow LED Pro Aquarium Power Filter’s one cartridge contains only a sponge-like floss envelope with activated carbon, the Deep Blue BioMaxx Power Filter and Tetra Whisper Power Filter look like the Aqueon model but have an additional sponge, and the Marineland Penguin Power Filter offers a high-surface-area bio-wheel that’s good for bacterial growth but not quite as good as ceramic stones. The AquaClear model is like a turbocharged version of the filter included in the Marina kit, as it has the same customization options but offers more room and higher-quality ready-made filter material.

“AquaClear is the number one filter. It sets itself above and beyond all others.”
—Pacific Aquarium’s Chi Cho

Aside from getting more effective filtration with the AquaClear system, you can replace the filtration media separately, so you can maintain much more beneficial bacteria during routine cleanings. For example, you can change the sponge one week and the carbon the next, and you can replace just half the bag of ceramic stones at a time. Replacing the one, all-encompassing cartridge in filters such as the Aqueon or Tetra model essentially removes all your beneficial bacteria, forcing your tank to re-cycle and potentially raising the ammonia levels in your tank. The versatile AquaClear design also leaves a ton of room for customization for more experienced aquarists who would prefer more ceramic rings and less activated carbon or who want to use a whole new medium altogether.

Most hanging power filters require once-a-month replacement of their cartridges, which are cheap individually but can get expensive over time. You can clean the AquaClear’s porous sponge with a simple rinse, which means you can replace it less often than sponges in other filters. And you can buy replacement carbon and ceramic stones in bulk online. We also appreciate the inclusion of a thorough and illuminating instruction manual, which does a good job of explaining how each stage of the filtration works and includes instructions for replacement (though many aquarists say you should never replace the BioMax or sponge, just rinse them in tank water once a month). Depending on whether you replace as often as the manual says you should (rather than just rinsing the filters), and on Amazon price fluctuations, you’re looking at maintenance costs of roughly $24 to $33 a year, similar to the costs of other multistep filters.

In our interviews with experts Seyffarth and Cho, both recommended overfiltering the tank but not by too much. According to Seyffarth, a good rule of thumb is to buy a filter for which the size of your tank is at the bottom end of the suitable range. For a 20-gallon tank, a filter meant for 15 to 40 gallons or 20 to 50 gallons would be a good choice. But a filter meant for 10 to 20 gallons may not be strong enough, and a filter for 30 to 60 gallons would produce a powerful current that may overwhelm your fish and keep your plants from growing. So we’re specifically recommending the AquaClear 30, which is designed to handle up to 30-gallon tanks.

A note on “self-cleaning” tanks

If you’ve seen advertisements for self-cleaning tanks that don’t require a filter, such as hydroponics systems or gravity tanks, be wary of overhyped marketing. Self-cleaning tanks sound great in theory, especially for the lazy aquarium owner, but they’re overpriced, tiny, and hard to keep, and they cause undue stress for your fish. And while a few buried flakes of fish food can cause a minor ammonia spike in a 20-gallon tank, those toxins can prove catastrophic in a tiny 2-gallon model. And only a betta fish could survive, but not thrive, in a tank that small.

Water conditioner

A bottle on the dresser says "Prime: concentrated conditioner, marine and fresh water."

When it comes to treating water so that it’s safe for your fish, Seachem Prime is the gold standard because it’s the most cost-effective dechlorinator you can buy. It’s the second most concentrated widely available dechlorinator, after Seachem’s saltwater-specific conditioner. Just one 16.9-ounce bottle treats 1,000 gallons of tap water, so you won’t need to buy another bottle for a long time.

Dechlorinators work through a process called reduction. This process adds electrons to dissolved chlorine gas (Cl2), which is toxic to fish, and breaks it into nontoxic chloride ions (Cl-). It also chops up chloramine (NH2Cl) into chloride and ammonia (NH3).

Just one 16.9-ounce bottle of Seachem Prime water conditioner treats 1,000 gallons of tap water.

Seachem Prime’s ultraconcentrated brew will also save you money in the long run. One ounce costs around 74¢, a little more than water conditioners from Aqueon, Tetra, and API, which run around 40¢ to 50¢ an ounce. But one teaspoon of each of those conditioners treats just 10 gallons of tank water, while a teaspoon of Seachem Prime is good for 50 gallons. Pacific Aquarium’s Chi Cho swears by the conditioner. “Seachem is just one level above the rest,” he said.

Water test kit

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Best Aquarium Heater Reviews

When you want your fish to stay warm and healthy, an aquarium heater is the essential gadget you need. If you’re having doubts about choosing the right product, we are here to help.

Fish don’t require too much attention, and your home is cozier and prettier with them. However, if you want to keep your little pets safe and comfortable, you should have a good aquarium heater. We have chosen several top rated aquarium heaters for you, and we hope our reviews and buying guide will help you make an educated purchase.

5 Best Rated Aquarium Heaters on the Market

Aqueon W Pro Heater

Most Popular Product

The Aqueon Pro Heater is a great model for people who are looking for affordability and efficiency in a single unit.

The 50W power output may seem as underwhelming to some people, but rest assured that it’s more than enough, especially when submersible heaters are in question.

As far as the setup goes, it couldn’t be any simpler. Thanks to the included suction cup, you can position the radiator wherever you want inside the aquarium in a matter of seconds.

When it comes to unique features, the monitor power light stands out as the most notable one.

It allows you to control and supervise the temperature levels so that it doesn’t overheat the water and cause severe consequences to the sensitive micro eco-system inside the aquarium.

The principle is pretty simple – green light means that the desired temperatures are reached, while the red light indicates an operation in progress.

The electronic thermostat is responsible for temperature regulation, and it works quite well. In fact, it’s accurate to within +/- 1 degree Fahrenheit.

The unit features an automatic safety shut-off, and an overheat protection system.

Bear in mind that the Aqueon Pro Heater is recommended for aquariums up to 20 gallons meaning it may underperform if installed in aquariums of bigger volume.

Some users have complained about the thermostat not working properly.

Eheim Jager Aquarium Thermostat Heater

Best Value for Money



  • Great value for money
  • TruTemp technology
  • Shock resistant


  • TruTemp tends to fail occasionally
  • Setup can be a burden due to the lack of info in the manual

View Price on Amazon

This model is a perfect example of a seemingly average-looking unit working like a charm.

It goes to show that aesthetics don’t mean a thing when it comes to functionality and efficiency.

The Eheim Jager heater is fully submersible, and it features a Thermo-safety control that prevents it from running dry.

As far as the safety features go, the most notable one is the auto shut-off function. While the auto shut off function doesn’t seem particularly impressive; you would be surprised at how useful and life-saving it can be.

The thing that separates this particular model from most of the others is the TruTemp technology.

It’s a pretty simple concept and yet incredibly effective. It recalibrates the unit in order to improve and increase the thermostat precision up to 0.5 degrees Fahrenheit.

If you’re looking for a consistent device with a sensitive thermostat, this might be the one. It will regulate the temperatures in aquariums that are up to 16 gallons in volume.

Make sure your aquarium isn’t bigger than 16 gallons because this unit won’t be able to cope with the larger ones. Last, but not least – it is suitable both for fresh and marine water.

The TruTemp technology may not work properly under certain conditions.

Cobalt Aquatics Neo-Therm Heater

Most Accurate Thermostat



  • Flat design (Aesthetically pleasing)
  • One of the most precise thermostats within this price range
  • Easy setup


  • The mounting suction cups are underwhelming
  • Tends to malfunction randomly

View Price on Amazon

Consistency is one of the crucial features of every water heater that’s worth looking into.

There are tons of units on the market, but only a small group of them are a worthy investment. The others are either inconsistent or plain bad.

The Cobalt Aquatics Neo-Therm is a well-respected model among enthusiasts due to its extraordinary thermostat consistency, precision, and efficiency.

The design is somewhat conventional, but it stands out thanks to its particularly thin body.

While other models tend to look bulky and cumbersome, especially in smaller aquariums, this one is almost imperceptible which improves the overall aesthetics quite a bit.

Durability is good, and the shatterproof design is responsible for preventing heavy damage which may cause severe consequences to the ecosystem within the aquarium.

However, what makes this particular radiator stand out is its extremely precise thermostat with 0.5 degrees Fahrenheit of tolerance.

In other words, you can rest assured that this unit will keep the water temperature at an optimal level at all times.

Once the temperature drops, the automatic thermostat switch will activate the heater and regulate the temperature within seconds.

The model works both in fresh and marine water; therefore, it’s suitable for a vast array of different eco systems.

Sudden thermostat malfunctions can cause fatal consequences.

Finnex Hang-On Electronic Controller Aquarium Heater

Best for Professionals

When it comes to professional high-end aquarium heaters, this model is a serious competitor to be one of the best units within this price range.

The thing that makes it desirable among devoted professionals is its all-titanium design.

As you can assume, due to the absence of plastic and glass parts, it’s regarded as extremely durable and able to withstand rough conditions.

The installation is as easy as it can be. All you have to do is apply the two included suction cups onto a glass surface, and that’s it.

Apart from the extra-durable design, its external controller is also one of the great advantages.

While many other models feature a scale that’s integrated into the body, this one uses an external device.

This way, you can adjust, calibrate, and fine-tune the temperature without having to dip your hands in water.

It may not sound particularly impressive for some people, but the external controller is quite convenient, especially if you’re in a hurry.

The LED indicators are well-designed and pretty comprehensive. This unit is suitable for aquariums of up to 120 gallons in volume, hence the professional compatibility.

The price may be regarded as a premium one, but it’s well-worth the investment. You can rest assured that this unit will keep your fish safe and water at an optimal temperature without any issues.

The fast-heating system can alter the water temperature dangerously quickly and cause issues.

Hydor In-Line External Heater – Original ETH

Top Quality



  • You can hide it
  • Special polymer heating system
  • Adjustable temperature with an ergonomic knob
  • Special plastic protection
  • Light indicator


  • Might overheat
  • Some complain about thermostat

View Price on Amazon

Many people are reluctant when it comes to buying external radiators because most of the ones that are available on the market are either of poor quality or insufficiently effective.

Either way, a vast majority of other models are underwhelming in performance and usually overpriced.

However, the Hydor In-Line heater is one of the rare well-designed external radiators for both marine and fresh water.

The biggest advantage of every external device is that you can hide it from plain sight.

However, it’s also a problem because you can’t have constant supervision and react properly when something goes wrong.

Even though it’s a two-edged sword, once you lay your hands on a high-end unit, you’ll realize that supervision isn’t even needed.

On the other hand, external models require frequent maintenance and checks.

The self-limiting PTC heating element is what makes this particular aquarium heater worth checking out.

It guarantees top levels of safety during performance and lowers the risk of overheating significantly.

As you can assume, overheating is probably the biggest no-no in the industry because it causes fatal consequences to the living beings inside the aquarium.

The price-to-quality ratio is great, and the installation is quite simple. If you’re looking to hide heating components, make sure you check this model out, it performs great.

Some people complained about the lack of durability and resistance to outside factors.

Aquarium Heaters Buying Guide

Before you purchase a heater, you have to be aware of its possibilities and general purpose. Many people make a common mistake and buy the first one they see or the most expensive one they can get.

Both of these methods are completely wrong because you’ll end up with either an unsuitable or overpriced product. To find the perfect model for your setup, you have to keep an eye on these things:

The Thermostat Specifications

The thermostat is probably the biggest variable in nowadays models. In other words, every company manufactures a unique thermostat meaning most of them are different and work in slightly different ways.

The first thing you should look for is precision. A vast majority of models can be calibrated up to 0.5 degrees Fahrenheit.

However, there are some that can’t go below 2 degrees Fahrenheit. In case you have tropical fish, the .5 tolerance makes a huge difference in consistency and preservation of your pet’s well-being.

Make sure you look for super-sensitive thermostats in case you have tropical species in your aquarium.

Submersible or External

An answer to a never-ending question about whether the submersible units are better than the external ones is yet to be answered. A lot of people make a big deal of it, but it’s more a matter of personal preferences.

If you’re looking to hide the heater outside the aquarium, go with the external ones.

On the other hand, some submersible models are small and thin meaning they can be easily hidden inside the aquarium, for example – under a rock.

Instead of thinking about aesthetics, make sure you’re buying an efficient and quality heater.

Size of the Unit

Even though it doesn’t seem as relevant, size of the model is a pretty important factor.

Avoid making an unusual size ratio between the fish tank and the radiator because it can lead to some issues. Truth be told, this is a minor issue, but regardless.


There are a few usual power categories of every model. The most common go from 25W up to 120W.

To calculate the best value for your aquarium, you need to account the room temperature, aquarium size, and volume of the water.

Usually, users should use a 25W heater for every five gallons of water to heat five degrees.

In case you have a particularly large aquarium, more than one radiator may be needed. The key with multiple radiators is to position them properly inside the tank to ensure that water is heated evenly.

Design and Maintenance

The design is usually a matter of personal preference, but you should always aim for the simple ones that allow easy access and thus offer easy maintenance.

Even though these devices don’t require frequent maintenance, it’s always beneficial to have the ones that are easy to clean, repair, and replace.

This way, you don’t have to disrupt the eco-system inside the fish tank by compromising it with excess motion, vibrations, and more.

The Price

Regardless of your budget, avoid the cheap models – it’s as simple as that. As we already said, low-cost units usually do more harm than good due to their poor design or even worse – low-quality thermometers.

Bear in mind; there aren’t any alarms to warn you something is wrong meaning you’ll only notice a malfunction when it’s too late.

The Benefits of Owning an Aquarium Heater

Many people ignore the fact that fish are cold-blooded entities that rely on external factors in order to survive. The biggest and most obvious element for their survival is optimal water temperatures.

Consequently, individuals that ignore these requirements end up with an aquarium full of dead fish after a while, especially if tropical species are in question.

Take a moment and check this article out, it will help you to avoid such unpleasant scenarios.

Health Benefits

As we said, many species require a precisely controlled environment in order to survive or behave properly. Even the slightest fluctuations in water temperature can cause immediate death in some cases.

Therefore, the mandatory thing to do is to keep the water temperature at optimal levels at all times. The best thing you can do is conduct research and find accurate information regarding the temperature tolerance of particular species.

That way, you will be able to fine-tune the water temperature in your aquarium accordingly.

Good Against Various Bacteria

The development of bacteria inside the tank is usually one of the biggest problems for the owners. The annoying thing is that they are hard to eliminate, especially the more resistant ones.

However, a vast majority of bacteria can’t tolerate temperature fluctuations. In simpler words, the difference of even one degree in water temperature can kill a large percentage of harmful bacteria.

Hassle-Free Adjustments

Some of the older models struggled with consistency, overheating, and integrity. Consequently, many of them malfunctioned in the middle of the night or caused a change in temperature randomly.

However, thanks to the modern technology, a vast majority of newer models keep the temperature as stable as possible, don’t overheat, and are trustworthy when it comes to durability and integrity.

Make sure you pay attention to the specifications when purchasing these devices. Check for tolerance, fluctuations, and materials used in production.


Having a pretty aquarium in your home is great. However, there are plenty of things you should think about before focusing on the aesthetic elements. One of those elements is the heater. It’s the crucial part of every well-planned aquarium, and it’s greatly beneficial for the fish.

There are plenty of models to choose from but beware of cheap copies because they will do more harm than good. It’s of utmost importance that you don’t spare money on these things because you’ll end up losing both the investment and your precious pets.

Take a look at the products we’ve reviewed in this article, and you might find the ideal one for your setup. They are all high-quality units with accurate thermostats, and some of them even include innovative technologies like TruTemp.


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2017 heater best aquarium

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Best aquarium heater for your fish tank 2017

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