Best Aquarium Heaters

Hydor T08203 looks somewhat unassuming. Sure, the housing is pretty sleek. The black finish is glossy but, at the same time, subtle and even relatively understated.

The entire unit measures 4 x 4 x 12.5 inches, which is pretty standard as far as these aquarium heaters are concerned. Its weight barely reaches one pound, so you'll be comfortable handling and placing this thing.

When you don't necessarily care about these heaters' aesthetics (which is understandable), this compact unit looks basically like every other aquarium heater you've seen before. That's not even remotely the case though. There's pretty much only one difference between this model and most of these heaters but that one difference is huge.

As far as we're aware, what we have here is the first aquarium heating appliance that comes equipped with the company's exclusive PTC tech. Using this PTC heating element, the system is able to self-limit, pretty much guaranteeing complete safety against overheating. All you have to make sure is that the ETH model is used in a vertical fashion to ensure correct operation.

Generally speaking, the technologies that are similar to this PTC tech are designed to be put onto return lines coming from various canister filters. That being said, this particular unit is easily adaptable and can be installed pretty much anywhere where heated aquarium water is a requirement (like with wet/dry sump pumps).

Hygger Submersible Pinpoint Aquarium Heater will make sure you have no issues keeping the tank at the right temperatures. Before anything else though, the product is available from 50 watts to 500 watts, so you'll definitely be able to find the one that fits your aquarium. We'll be reviewing the 100-watt model but, aside from how much power the unit draws and uses, there are no differences between these models, meaning that what we're writing here will be relevant towards them all.

First, the product looks somewhat clunky and awkward but that's not something that we usually hold against aquarium heaters. More often than not, nobody cares how these heaters look, although we can appreciate it when some thought has been put into the unit's aesthetics.

Before anything else, this appliance is tough. Its IPX8 rating means that you can submerge the unit without worrying about its circuitry. The two suction cups that come supplied with the package will let you comfortably mount this thing onto most tanks. All you have to do is make sure the unit is placed where the water flow is considerable, that's how you'll be able to secure the same temperature throughout the entire aquarium.

The heater comes equipped with this separate controller that will let you easily and comfortably adjust the temperature from low to high without even taking out the unit from the tank. You'll be able to regulate the temperature anywhere between 32 and 104 degrees Fahrenheit, meaning that this model will prove suitable for most aquariums that house most fishes.

Fluval A774 appears pretty basic. The unit is anything but though. The streamlined construction and the trim but somewhat uninspired build make this little appliance look quite bland. Surprisingly enough, this "bland" notion is divorced from reality. There's pretty much nothing bland about this heater.

First and foremost, the company's VueTech tech ensures precision and secures safety. During normal operation, the temperature readouts will change color when the water inside the tank varies +/-2 degrees Fahrenheit or more from the temperature that you have pre-set.

Should any external heat sources (like chillers, for example) cause the temperature inside the tank to fall or rise more than 5.5 degrees Fahrenheit, the unit's screen will flash to indicate potential risks. You can also change the values to Celcius.

That's not everything that Fluval A774 is packing on the safety front though, not even remotely. Equipped with integrated fish guards, the unit is as tough as they get. Its protective casing will make sure that fish and various invertebrates are unable to come into direct contact with the unit's core. At the same time, the glass sleeve is pretty tough too, protected from shocks that large fish species are usually able to cause.

VIVOSUN Aquarium Heater is hands-down the sleekest, most modern-looking unit on this list. Its slim profile measures 15.5 x 3.3 x 1.7 inches, meaning that the heater will barely be taking away any space at all.

The smooth finish adds to the unit's aesthetic, which is nice even though these heaters can look however they want and still attract customers because these things are not about aesthetics first.

Of course, these tank heaters ought to be safe, comfortable, and reliable before anything else but the people behind this product have been able to check these demands off too.

From the safety standpoint, the unit's IP68 protection rating means you can submerge this compact appliance as deep as you want without worrying about its components.

In addition to that, the titanium tube will be able to last no matter what. It is explosion-proof, so you won't have to worry about sudden and extreme temperature changes causing anything. The tube's also corrosion-resistant, meaning you can put this thing inside saltwater aquariums (also aquaculture, most glass containers, and hydroponic systems but that's beside the point).

The anti-flaming casing will be preventing fish from getting too close to the unit, so you won't have to take various aquatic creatures' safety into account too. At the same time, the overheat and water shortage protection mechanisms will be able to prevent any accidents.

Aqueon 100106251 Preset Heater is fairly interesting but somewhat weird too. Though the unit looks the part, the heater is not as sophisticated as the units we've reviewed above. In fact, you could call this heater pretty basic.

Of course, the price reflects that. Since the product costs less than 10 bucks whereas most aquarium heaters cost somewhere between 35-70 bucks, you cannot measure this unit's value using the same standards.

Generally speaking, we've no major qualms with this product except that the supplied suction cups lose their adhesive properties pretty quickly, so you'll probably have to replace them in a few years. That's a shame since, otherwise, these cups are quite nice and let you place them vertically or horizontally within the tank. Apart from that though, there's not much here to complain about.

First off, the unit is tiny. Measuring 3.5 x 1.5 x 7 inches, you won't have to worry about this heater taking away that precious aquarium space from aquatic creatures. Also, the unit weighs 7 ounces, so you'll be able to comfortably pick up and move this thing when necessary.

You won't have to do that often though since the heater comes pre-calibrated at 78 degrees Fahrenheit. In other words, you won't be able to regulate the temperature.

On paper, that's kind of a bummer since you'd probably want that option but, generally speaking, that's appropriate and more than comfortable for most tropical fish species, meaning that the absolute majority of customers will have no issues with the pre-calibrated temperature.