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 Top Rated Aquarium Heaters on the Market
Aqueon 50W 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
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
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
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.
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.
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.
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.