Stephen is an owner of several aquarium supplies shops in New York. Like no one else, he knows how to pick the perfect fish tank or any aquarium accessory from pump to artificial decorative plants.
Last updated: August 19, 2022
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Fish can`t regulate their body temperature. In the wild, they naturally breed in locations where they can survive. Of course, when you buy fish for your tank at home, you need to take precautions to ensure that your fish are warm and comfortable to ensure their survival.
To maintain the temperature of your home fish tank, the best aquarium heater is a must. Of course, there are several features to consider when choosing a fish tank heater. The temperature range ensures that your fish have the perfect conditions while the size and tank capacity tells you which aquariums the heater is best suited for. If you’re in need of the best aquarium water heater but don’t know where to start, the following information can help.
More features: dual sensors, fully submersible, toggle lever, LED screen, integrated fish guard, saltwater compatible
The Fluval E300 is one of the best submersible aquarium heaters on the market, thanks to the waterproof design that allows you to position it as needed in your tank. This model features simple controls, a digital display for either Celsius or Fahrenheit, and a microprocessor with dual sensors for the most accurate readings possible. There is also a colored alert system that shows green for safe temperatures and changes to blue when it’s too low or red for too hot.
Anyone who wants the best 300-watt aquarium heater that is extremely accurate and easy to use will love this model, thanks to the simple controls, color-coded readout, and independent mounting bracket.
Why did it make our list?
There were a lot of fantastic features offered by this aquarium heater that we loved. This includes the colored display that changes with any alterations of the water temperature, the wide temperature range, and the fish guard that protects your little swimmers from harm. The price is a bit high but worth it when you consider all the features this model has to offer and the durability of the heater.
What is not ideal about it?
Though this is one of the best digital aquarium heaters on the market, we noticed some issues with the included instruction manual. Rather than placing it vertically as is stated in the manual, it is best to mount it at a 45-degree angle, preferably with the end facing the filter intake. This helps the heater maintain an even temperature without it reading a low flow issue that could disrupt how it works.
More features: submersible, 5.6 ft cord, saltwater compatible, automatic shut-off, TruTemp dial
This aquarium heater by Eheim Jager is a fully submersible model that includes fantastic features, including the top temperature dial for easy adjustments and an on/off indicator light so you always know when it’s running. It also has some great safety features, like shock-resistant, shatterproof glass, double sealing, and heat protection. The extra-long cable is double-insulated for extra protection.
The Eheim Jager Aquarium Thermostat Heater 125W is the perfect heater for medium-sized tanks since it is made of shatter-proof glass, has an auto-shutoff for low water levels, and is fully submersible. It is also easy to install using the included clamp and suction cups.
Why did it make our list?
We loved how accurate this heater is since all it takes is the right calibration and water circulation to maintain the perfect temperature at all times. It is also easy to use, with simple dials at the top of the heater that makes it easy to adjust the temperature as needed. Best of all, this model is well-built and strong, so it won’t crack or break, even with some rough handling.
What is not ideal about it?
The Eheim Jager Aquarium Thermostat Heater 125W is a decent aquarium heater 55-gallon model for a great price, though we did find it a bit tricky to calibrate it before you can put it to use. The instructions for this are somewhat vague, so it may take some searching online for videos, as well as some trial and error at home to get it done properly to maintain your tank’s temperature.
More features: automatic safety switch, 6 ft cord, top dial
The Marineland Precision Heater is a powerful 300-watt aquarium heater designed for 75-gallon fish tanks. It has a ton of great features, like a handy dial on the top for easy temperature adjustments and a glass thermometer so you can always see where the tank is at. It also features a thermal switch to shut off the heater when it has reached the right setting and on again as the tank cools off.
This model is great for those who want the best saltwater aquarium heater that is built to last. The advanced heating element uses a mesh heating element with a mica core for the best heat transfer possible.
What stands out?
This freshwater aquarium heater is well-made, with durable materials, a thermal switch to turn it off if it gets too hot to avoid cooking your fish, and an advanced mounting bracket that keeps it firmly in place on the side of the tank within easy view. We also liked that it included a lifetime warranty, which ensures that the company stands behind its product and will replace it if it fails.
What cons did we manage to find?
One issue that we noticed with the Marineland Precision Heater is that there have been instances of water condensation building up in the glass of the unit. Though this hasn’t caused any issues with the heater’s performance, it still shouldn’t be occurring. The heater also isn’t entirely consistent, though it usually heats within a degree or two to what you set it to, so the dial may need to be adjusted accordingly.
The Tetra 26445 Fauna Aquatic Reptile Heater is one of the easiest aquarium heaters that you can purchase. This is because it has a preset temperature setting of 78 degrees Fahrenheit, so all you need to do is mount it into the tank and plug it in. The case around the heater is durable plastic, with an 8-foot cord and two large suction cups to hold it in place wherever you want it.
This is the best 100-watt aquarium heater for those who like to keep turtles, frogs, newts, and other reptiles in their home. It is built to last, even with active animals that may knock the heater around during their play.
What do we love it for?
Our favorite feature that the Tetra 26445 Fauna Aquatic Reptile Heater has to offer is its durability. It includes a thick plastic cage over the heater itself, which offers protection to prevent any damage. It also has openings at the top that allow you to position the cord on any side to reach the nearest outlet with ease. The cord is also 8 feet long for added convenience.
What were we disappointed with?
One issue we noticed with this small aquarium heater is that it has a thermostat that is already preset for 78 degrees Fahrenheit. Though this is fine for turtles and other reptiles, it may not be the best option for every aquatic animal you have in your home. This limits how this heater can be used. The suction cups may also not hold as well as intended with rambunctious turtles.
More features: LED indicator, submersible, automatic shutoff, shatter-resistant
The Aqueon Preset Heater is a compact model that fits nicely into any small 30-gallon tank. It includes a preset temperature of 78 degrees Fahrenheit, so you don’t need to adjust any settings to use it. This heater is made of shatter-resistant glass and is fully submersible. A LED light on the side of the unit comes on when it’s running and turns off when the water is heated to the proper temperature and triggers the auto-shutoff.
For those on a limited budget who still want a decent heater for their aquarium, the Aqueon Preset Heater may be a good option. It has a great low price without sacrificing durability.
What do we love it for?
We found this aquarium heater to be one of the easiest models to use since you only need to suction it to the glass and plug it in for it to do its job. It turns on and off as needed, with no setting adjustments necessary to keep your fish happy. The great low price fits into any budget, plus this allows you to keep a few spares on hand.
What were we disappointed with?
The main downside we noticed with this heater for aquariums is that the specified preset temperature isn’t entirely accurate. It is actually designed to heat your tank about 5 degrees Fahrenheit above your room temperature to a maximum of 78 degrees. This means that the colder your home is, the cooler the tank will be unless you add an extra heater to the tank, which not every tank will have room for.
More features: LED indicator, shock resistant exterior, automatic shut off
Those who need the best small 10-gallon aquarium heater may want to check out the Tetra HT Submersible Aquarium Heater. It is fully submersible, with both horizontal and vertical installation options, and an automatic temperature setting of 78 degrees Fahrenheit. This 50W aquarium heater also features an indicator light that turns red when heating and green when the temperature is reached.
This little aquarium heater is best for those with aquariums that are between 2 and 10 gallons that also include a lid. This helps maintain the proper temperature for a more comfortable environment for your fish and requires the heater to run less often.
What makes it stand out?
Our favorite feature that the Tetra HT Submersible Aquarium Heater has to offer is its ability to be installed both vertically and horizontally. Most models need to be upright, which can be quite limiting, depending on the dimensions of your tank. This one can be placed however you need it to fit the tank and the other accessories inside of it to give your fish the most room.
Which disadvantages must you keep in mind?
Though this model is fine for 10-gallon tanks, it is a bit too big for the tanks on the smaller end of its acceptable range. This means that your fish in a small 2-gallon tank won’t have as much room to swim around, so it is best used on a bigger tank if possible. We also noticed that the suction cup doesn’t have as strong a hold as expected.
More features: submersible, push-button adjustment, shatterproof exterior, automatic shut off, LED screen
The Cobalt Aquatics Neo-Therm Pro is an electronic thermostat with a huge temperature range of 68 to 94 degrees Fahrenheit, though you likely won’t need to go that high for most of the fish in your tank. It includes an LED display that tells you the temperature you’ve set and the water’s temperature at the same time, plus it has an auto-shutoff to prevent overheating the water and cooking your fish. The shatter-proof outer case is durable and slim.
For those looking for the best submersible aquarium heater, this may be a good choice. It can be positioned both vertically and horizontally for the perfect fit and the best heating results.
What are our favorite features?
One of our favorite features that the Cobalt Aquatics Neo-Therm Pro has to offer is the dual temperature readings. This shows you the current temperature of the tank as well as the temperature that you’ve chosen, so you can easily see any discrepancies between these two. It also has a super flat design, which reduces how much space it takes up in your tank, leaving more room for your fish.
What could be better?
This Cobalt aquarium heater is a bit pricey compared to some of the other models on the market. This could be due to the build of the heater and its amazing features that aren’t all offered with other models, though this still may put this model out of some people’s price range. It also needs to be fully submerged at all times since the temperature sensor is at the top of the device.
More features: 4.9 ft cord, temperature control knob, LED indicator, automatic shut off, shatter-proof exterior
Not only is the FREESEA Aquarium Fish Tank Heater a great model for Bettas and other freshwater fish, but it can also be used as a heater in a saltwater aquarium for all your aquatic creatures. It features a temperature dial with a range of 64 to 93 degrees Fahrenheit, automatic functioning to maintain the temperature at all times, and auto-shutoff for overheating protection. It is also well-built to increase durability and safety.
This aquarium heater has been upgraded from the previous version to include 2mm Quartz glass. This prevents it from breaking, no matter how aggressive your fish are, plus it is double-sealed to protect your hands and fish from scalds.
Why did it make our list?
This model is quite durable and easy to use to give your aquarium the perfect water temperature for your fish to thrive. That’s why we love that this company included a digital thermometer with the heater, so you can monitor the water temperature at all times to be sure the heater is working as it’s supposed to. You can place these pieces wherever needed for the most accurate readings possible.
What is not ideal about it?
Though this aquarium heater has a wide temperature range, it only goes up in 3 to 4-degree increments, so you can’t adjust it by only a degree or two if needed. This doesn’t necessarily mean that you can’t get it to the temperature you want, though we did find it a bit limiting in the options available. The power cord is also a bit short at only 4 feet.
More features: LED screen, automatic shut off, 5 ft cord length, corrosion-resistant, built-in temp controller
The hygger Fast Heating Titanium Aquarium Heater is a 500-watt model that’s designed for larger tanks between 60 and 130 gallons. It includes a fully submersible titanium heater surrounded by a black ABS plastic protective guard. It has a range of 70 to 94 degrees Fahrenheit, with an auto-shutoff for overheat protection. Outside the tank is the LED temperature controller for setting the temp you want and monitoring the current temperature of the water.
This is a great model for those who need a powerful heater to warm the water in a huge 125-gallon tank. It works well, with a bright display for consistent temperature monitoring.
Why are we impressed?
This model has a design that is unique to a lot of other models that we looked at. The controller part of the device that allows you to set the temperature is installed outside of the tank, so you can make the necessary adjustments without putting your hands wet. It is also made of high-quality, durable materials with a variety of safety features to keep your fish safe.
What negatives must you be aware of?
This is an expensive model, which may be a bit too costly for some fish owners. Of course, it is a titanium aquarium heater with memory functions, auto-shutoff, and other great features, so it may be worth the price. It is also tricky to install since the plug comes out of the top of the digital controller and isn’t very long, which makes it difficult to plug into any outlet low to the ground.
More features: knob temperature control, IP68 waterproof, saltwater compatible, LED light, automatic shut off
Those who need a simple aquarium heater that works well and doesn’t cost a fortune may want to check out the Uniclife Aquarium Heater HT-2100. It has a temperature range of 68 to 93 degrees Fahrenheit, with a visible display that shows you the tank temperature for quick monitoring. Other features include a red indicator light to show when it’s running, IP68 sealing for waterproofing, and shatterproof glass for durability.
This is a great choice for those who need a versatile heater for their aquariums. It can be placed vertically or horizontally using the 3 included suctions cups.
What stands out?
This heater has a great low price, plus it has some great features that we feel make it worth trying out in your smaller tanks of up to 25 gallons. It is easy to use thanks to the simple red dial at the top of the heater for quick temperature adjustments. It also has an indicator light to let you know when it’s running and an auto-shutoff for when the set temperature is reached.
What cons did we manage to find?
The biggest downside that we noticed with this aquarium heater is that it can’t be set to a specific temperature. The settings go up 2 to 4 degrees at a time, so you need to spend some time fine-tuning it to be sure you have it set at the temperature your fish need to thrive. You may also need an additional thermometer for this to make sure the reading you’re seeing is accurate.
Things to Consider
Even the least expensive fish available need to have a proper home to survive in. That’s why adding an aquarium heater to any aquarium is so important. It ensures that the water is at the right temperature to keep your fish comfortable and swimming happily. These aquarium heaters also come in several power levels, sizes, and capacity ranges, so you can get the perfect one for any aquatic life you have in your home.
Is Aquarium Heater Necessary?
An aquarium heater is necessary for all of your aquatic pets since they are used to certain temperatures
Trusted SourceAquarium Temperature ControlA good aquarium temperature range is 76° to 80°F (25° to 27°C). A reliable heater is necessary for most tropical fishes.
in the wild. In fact, most tropical or saltwater fish prefer warmer temperatures, so keeping the water between 75 and 80 degrees Fahrenheit will ensure that they will thrive. Even the normal temperature of our home is too cold for them, plus there are seasonal temperature changes that cool things down in the winter or require the use of air conditioners in the summer. A heater will maintain the water’s temperature for more comfortable conditions for any fish or reptiles you keep.
Temperature regulations for fish
If you’re going to have an aquarium in your home, you need to stock it with fish that can handle the temperatures you set
Trusted SourceSelecting a pet fishPets are an important part of the American household. Your pet-owning experience will be most enjoyable if you carefully consider which pet best suits your family, home and lifestyle. Unfulfilled expectations are a leading cause of pet relinquishment, so make an informed decision. Take time, involve your family, and give careful consideration to the following questions.
. Not all fish like the same conditions, so you need to choose carefully. For instance, there are several cold-water fish species, like Bloodfin Tetras and Endler’s Livebearer with wide temperature ranges of 65 to 82 degrees Fahrenheit. The Odessa Barbs and Celestial Perl Danios prefer things a bit more stable, between 73 and 79 degrees F. Tropical species like Molly fish prefer things a bit warmer, so keeping your tank between 75 and 85 degrees F is a must.
How to Install Aquarium Heater
Depending on the type, aquarium heaters can be installed outside and inside the tank using a vacuum cap
Installing an aquarium heater can vary from model to model, though most of them include similar steps. Attach the suction cups or other mounting pieces to the heater. Then place the heater at the back or side of the tank, pressing the suction cups into the glass for a firm hold.
Be sure there is an outlet nearby to plug the heater into. Some models can be placed vertically or horizontally, so you can position them however they fit best to avoid the substrate and other tank items.
Leave the heater in the water to adjust to the temperature before plugging it in. Once it has been acclimatized, plug it in, set the temperature you want for the tank if possible, and turn it on.
For the safest heater, choose one made of durable materials to avoid cracking or damage if it gets knocked by the aquatic life in the tank. Be sure the heater is as submerged as instructed to avoid damage to the device. Place it near the filter to ensure the proper water circulation for the most accurate temperature possible.
How to Pick the Best Aquarium Heater
If you’re unsure what to look for in a new aquarium heater, the following sections can help determine what you need.
You can opt for various aquarium heaters that can be suited to your tank size and water type
There are two main types of aquarium heaters, including substrate and submersible heaters. The substrate models are best for reptiles and plants, so we didn’t include these in our reviews. Submersible models are designed to be used underwater, so are great for all species of fish, as well as turtles, snails, and other water dwellers.
The best 25-watt heater for aquariums obviously isn’t as powerful as a 200-watt model, so the lower-powered models are best for smaller tanks. If you need more power for a huge aquarium, you can choose models like the hygger Fast Heating Titanium Aquarium Heater. You can also use two heaters in a single large tank for more even heat distribution if necessary.
The tank capacity is something else to consider when choosing a new aquarium heater. The larger the tank, the more powerful the heater needs to be, so you won`t be able to use a 50-watt heater for a 300-gallon tank. The more water the tank holds, the more powerful the heater needs to be for the most efficient heating possible.
Some aquarium heaters, like the Aqueon Preset Heater, have a preset temperature, so all you need to do is install it in the tank and plug it in. Other models have a range of temperature options, like the Cobalt Aquatics Neo-Therm Pro. This allows you to adjust the temperature as needed for the aquatic pets in the aquarium and the conditions of your home. The wider the temperature range, the more options you have on the fish you can keep.
Many of the aquarium heaters on the market include some safety features. One to look for is an automatic shut-off when the water level drops below the acceptable level for the heater or when it starts to overheat. Some heaters are made of glass, so shatter-proof material is a must to prevent a broken heater. The Tetra HT Submersible Aquarium Heater also has a shock-resistant exterior for even more protection.
Indicators and controls
Depending on the type, aquarium heater features simple dial and one LED indicator when the device is working
Most of the models in our reviews have some sort of indicator, which is designed to show you when the aquarium heater is running and when it has shut off, usually due to the proper temperature being reached in the tank. This can be a simple indicator light or a more elaborate one, like the one on the Fluval E300 that is green for safe temperatures, blue for too cold, and red for too hot.
The durability of the heater you use in your aquarium determines how long it will last and how safe it is. The stronger the material, the longer it will last and the less chance there is that it could harm your aquatic pets.
A good warranty will cover any issues your heater may have. Though a 1 or 2-year warranty is fine, the Marineland Precision Heater offers a lifetime warranty, so you won`t have to pay to replace a faulty heater.
Heaters come in varying sizes, so you also need to look at this when choosing one for your tank. If it doesn`t fit well in the tank because it sticks out the top or takes up too much space, it won`t be usable. Check the dimensions of the tank and the positioning options for the heater before choosing one.
Not everyone has an outlet right next to their aquarium, so a longer cord is best. If it is too short, it won`t reach, requiring the use of an extension cord or new placement for your aquarium.
An aquarium heater should be placed on the inside of the tank beneath the surface of the water. Most models need to be fully submerged, though some have the top areas above water, so be sure to check the instructions for proper installation. It is also best to place it near the filter for better water circulation and more accurate readings.
There are a few ways to tell if the heater is working. Some models have an indicator light that turns on when it’s running and off when it’s not. Monitoring the temperature of the tank water to be sure it is consistent also tells you the heater is working since the temperature will drop if it fails.
Improper installation is one way to break an aquarium heater since it may be trying to heat the air instead of the water, forcing it to run constantly until it overheats and shorts out. Being too rough with the heater or placing it in a tank with aquatic life that is somewhat aggressive can also cause damage to the heater.
With so many aquarium heaters available, it can be hard to choose one. To help you decide, we have a few favorites we`d recommend.
Our top choice is the Fluval E300, which is a 300-watt model designed for tanks up to 100 gallons. This model is fully submersible, with a wide temperature range and dual sensors for accurate readings. This heater also includes an LED screen with a color-coded display.
For the best aquarium heater on a budget, the Aqueon Preset Heater has a great low price and a set temperature of 78 degrees Fahrenheit. It is easy to install, with an LED indicator, and shatter-resistant glass.
Aquarium Temperature Control
A good aquarium temperature range is 76° to 80°F (25° to 27°C). A reliable heater is necessary for most tropical fishes.
Pets are an important part of the American household. Your pet-owning experience will be most enjoyable if you carefully consider which pet best suits your family, home and lifestyle. Unfulfilled expectations are a leading cause of pet relinquishment, so make an informed decision. Take time, involve your family, and give careful consideration to the following questions.