all types of fish tank

what is the best aquarium heater 2021?

The aquarium heater is an essential accessory for any aquarium as fish in an aquarium can’t maintain their body temperature according to their environment. so it’s important to have an electric heater in your aquarium except if you have a cold-water fish.

Almost all modern heaters heat the water automatically as they have a temperature sensor and can sense the temperature inside the aquarium, therefore, maintain the temperature to suit the fish. You can use one heater or multiple, depending on your setup.

best aquarium heater
best aquarium heater review

types of aquarium heater:

There are different types of heaters such as: 

  • In-filter heater: this kind is placed inside the filter of the aquarium and also works with it.
  • Inline heater: this one placed inside the sump to heat the fish tank to a perfect degree for the aquarium inhabitants.
  • Filter heater: this kind is built in the filter. So it’s great as you don’t have to buy separately the heater and the filter.
  • Submersible heater: this kind is submerged into the water and the ideal place for it is to be on of the corners and near to the pump or the filter output so the heat move with the water all over the tank.

Now let us take a close look at the heater size, heater wattage per gallon, heater placement, best heater, and a lot more.

aquarium heater size:

For the heater wattage, the basic rule of thumb is to use between 2.5 and 5 watts per gallon of actual water volume in the aquarium. So this depends on the size of the tank. Here is a heater size guide table that demonstrates the required heater size for different fish tanks.

Tank size Heater size
5-10 gallons 25-75 watts
20-25 gallons 50-200 watts
40-50 gallons 100-400 watts
65-75 gallons 200-600 watts


aquarium heater placement:

Once you have filled the tank with water now you can set up your heater wherever you find it suitable like on the right of the glass or on the left. But the best location is to place it near the maximum water flow. place it near the filter outlet or inlet, in the stream of a powerhead, or next to an air pump where the water flows directly past the heater. Finally, make sure it doesn’t touch the walls if you place it in the backside of the tank because the heat difference may crack the heater glass.

important features when looking for the best aquarium heater

Let’s take a look at some important features you need to consider when looking for the heater that’s right for your fish tank :

Available watts:  It determines the ability to heat and maintain the desired temperature in the aquarium. So you should get the right heater size according to your tank size as we mentioned in the header guide table in the top.

Adjustable temperature: if you want to change the setting of the heater to select the maximum temperature or the temperature that is perfect for your aquarium. Some heaters come with fixed settings not let you adjust the temperature so you have to select the heater that gives a temperature that suits your aquarium or the heater you can adjust its settings.

Access to the controls: You should look for heaters with a large control knob that is easy to grab and twist when submerged.

Temperature readability: you should look for a heater that allows you to easily read the temperature of the water.

Safety features: make sure the heater you’re buying is fully submersible and able to shut down automatically when the water level gets too low or the temperature in the tank gets too high.

the best aquarium heater brand:

Tetra HT:  Cheap and Reliable Popular & Best Submersible Heater.

Eheim Jager Heater – Most Popular & Durable

Aqueon Pro Heater – For Safety Conscious People

Aqua Top Quartz Heater– Genuine & Affordable

Hydor In-Line External Heater – Has the Best New Technology

 the best aquarium heater review

ProductProsConsBuy Now
Aqueon Adjustable Pro Aquarium Heater

1 - The electrical thermostat automatically switches itself off if the heater is not in the water, and resets itself to resume working when placed back into the water.

2- The heater can be placed vertically or horizontally inside the fish aquarium.

3- Come With a large knob to help you adjust the temperature.

4- The red indicator light means the heater is doing its job of heating and it becomes green once the aquarium reaches the set temperature.

5- It is available in models from 50 to 300 watts.
1- Expensive

2- Not for marine water

3- The temperature reading is only in Fahrenheit as compared to others that shows both Celsius and Fahrenheit.
Eheim Jager Aquarium 25 - 300 watts Thermostat Heater 1- Widest Range of heaters in watts: If you need 25 or 300-watt heaters.

2-Thermostat control provides protection against running dry. With the water level dipping too low, the heater switches off automatically.

3- Suitable for use in marine water

4- The indicator light provides at-a-glance monitoring.
1- Mediocre Customer Service

2- It’s very long, and it may be difficult to set horizontally.

3- Higher Price than Aquatop, Tetra HT and Hydor Aquarium Heater
Buy Now
Aquatop Quartz Glass Submersible Heaters1- Accurate Temperature settings, simple to set up and powerful.

2- Easily adjustable temperature settings and the highly visible display.

3- low price
1- Only 1 Year WarrantyBuy Now
Tetra HT Submersible Aquarium Heater With Electronic Thermostat1- Small Size: Best for Betta fish tanks and other small aquariums

2- The indicator lights turn red when heating and the green light indicates the set temperature has been achieved.

3- The built-in electronic thermostat automatically maintains the water temp at 78° F that is in the
1- there is No Dry-Safety. So avoid plugging the heater into an electrical outlet until it is placed inside the aquarium.

2- Only available in 50, 100, 150 watts
Buy Now
Hydor Submersible Glass Aquarium Heater 1-available 25 -200 watts

2- Shock resistant & High resistance – the 1st shatterproof heater.

3- You can position it horizontally, vertically, and completely submerged.

4- No damage in case of running dry.

5- Affordable.
1- Precision Problems are reported by some customers.Buy Now

Digital aquarium heater:

Digital heaters are the best to control and adjust your aquarium temperature. They are precise and easy to read. There are a lot of brands of digital heaters that are available online, let us see some of them.

Aquatop 200 watt1- Power: 200W

2- Voltage: 110-120v/60hz

3- Temperatures adjustable between 20c-34c/68-93F.

4- Dimensions: 1.25" x 1.25" x 10"

5- Suitable for tanks up to 50 Gallons
Buy Now
Hygger 500W 300W Aquarium Heater
1- Fast heating and reliable, fully automatic control.

2- Suitable for freshwater and saltwater aquarium use.

3- The controller with memory function in case of power-down.
4- Durable and explosion-proof quartz glass heater tube.

5- Very easy to install and use.

6- stop and restart heating
Buy Now
SUNSUN Aquarium Submersible Heater 1- Accurate constant temperature, 18-34℃ free adjustment.

2- Anti-collision protection case to avoid heating collision and burn, protect the fish.

3- Submersible, waterproof double insulation, durable and safe design.

4- The compact design does not take up space in the fish tank and is more beautiful.

5- External temperature control switch for convenient temperature control.
Buy Now
Fluval E 50w Advanced Electronic Heater
1- Continuously monitors and displays aquarium water temperature in real time

2- Intelligent digital microprocessor monitoring system with dual sensors

3- Ensures the safety and well-being of your aquarium inhabitants

4- Precision temperature control allows settings in 0.5-degree increments

5- Integrated fish guard provides advanced protection
Buy Now

Titanium aquarium heater:

the Titanium heaters are made from titanium instead of glass and are much stronger, but also will cost more. Titanium heaters are typically more of a premium type of heater and will come with a controller and temperature probe. The addition of the probe allows you to measure the water temperature away from the heater, giving you a more stable overall temperature. The probe will tell the heater when to activate the heating element to warm the water and shut it off then you hit the right temperature.

 the best titanium aquarium heaters: 

ProductFeaturesBuy Now
hygger Titanium Aquarium HeaterDigital Submersible Heater with External IC Thermostat Controller and Thermometer.

Available sizes:
50W (5-10 gallon)
100W (10-25gallon)
200W (20-45 gallon)
500W (60-120 gallon)

Buy Now
Titanium heating system with digital controller1- Digital Heater Controller - accurate and precise to +/- 0.5° F

2- With Safety Guard

3- Smart Memory Chip - to reset your temperature settings after a power failure
Buy Now
Finnex Aquarium Heater 1- Stable temperature environment for your aquarium, eliminating temperature swings

2- Can be used with freshwater and saltwater

3- Protective heater guard wrap, to reduce harm to livestock and equipment

4- Includes suction cups to secure the titanium element in preferred locations
Buy Now
Won Brothers HT Titanium Heating Element1- Used for glass aquariums between 60 - 100 gallons

2- Titanium heating element offers an excellent chemical resistance in saltwater or freshwater

3- Unbreakable, corrosion-resistance heating element

4- Fast heating, durable and reliable
Buy Now

Sometimes we hear that 100-watt aquarium heater is the best or many people prefer, so let us check this by ourselves.
let us see the best 100-watt aquarium heaters with different brands.

100-watt aquarium heater :

ProductFeaturesBuy Now
Aqueon Pro Adjustable Heater, 100W1- It is a fully submersible 100W heater

2- Temperature level between 68 - 88 F and has a sign light that switches off automatically

3- Suitable for 2- and 30 gallon aquariums, both fresh water and saltwater aquariums
Buy Now
Cobalt Aquatics Flat Neo-Therm Heater1- Also is a fully Submersible heater come with Adjustable Thermostat

2- shatter proof design

3- Temperature level between 66 to 95 F
Buy Now
Finnex Hang-On Electronic Controller Aquarium Heater1- Temperature between 70-92 F

2- There is an indication light for power as well as for heater

3- Suitable for aquariums up to 30 gallon

4- Contain heater controller with titanium tube
Buy Now
EHEIM Jager Aquarium Thermostat Heater 1- When water level gets too low it will turn off automatically

2- used with fresh and marine water, made of shatter proof glass
Buy Now
Orlushy Aquarium Heater1- Fully submersible heater

2- For marine reef fish tank sump

3- suitable for 15 and 30 gallons aquariums

4- Contain a Sensitive and reliable thermostat maintains uniform temperature.

5- Automatic turnoff when the temperature is reached
( 89 F )
Buy Now

Now, How you can choose the right heater for your fish tank and how you know if your aquarium needs a heater or not.
Maybe it’s confusing for beginners to know if their aquarium needs a heater or not so let us see when you use a heater inside your tank.

in a nutshell, if you keep your home at a temperature level lower than 78-80°F, in this case definitely your aquarium needs a heater because most fish are cold-blooded so they use the environment around them to balance the temperature inside their body and what helps to provide them this balance is an aquarium heater.

Well, now you know that you need a heater inside your fish tank so how to get what suits the size of your aquarium.

Aquarium heater wattage per gallon:

The rule of thumb is 5 watts of heat per 1 gallon of water. so under this rule, if you have a 20-gallon fish tank the best heater for you will be 100 watt type. but if live in a cold place maybe you need to raise the wattage of the heater to be 150 watts.
Below, there is a table that shows you the wattage of the heater you need if you want to raise the temperature of the tank 10 or more than 10 degrees of the room temperature.

Tank sizeraise temp by 10 degreesraise temp more than10 degrees
5 gallon25 watt50 watt
10 gallon50 watt 100 watt
20 gallon100 watt150 watt
30 gallon150 watt200 watt
40 gallon200 watt300 watt
55 gallon300 watt400 watt
75 gallon400 watt600 watt

Q & A  about aquarium heater

What is the heater size for a 55 gallon aquarium?

A good rule of thumb to follow is that your aquarium heater will need to output at least 3 to 5 watts of power for every gallon of water. So for a 55 gallon aquarium and consider you want to adjust the temperature of the tank to be like the room temperature in this case you need a 275-watt heater.

 How to install an aquarium heater?

You should know where to place your heater, Most suggest placing your fish tank heater where the water flows in and out of the filter. If your tank is larger than 40 gallons maybe you need two separate heaters.
Before you set the temperature for your heater you should know the perfect temperature for your fish.

Once you set your desired temperature turn on the heater. Typical heaters will have a monitor light that indicates whether the heater is working if the light is on.

How do I know if my aquarium heater is working?

The first step is by checking the light:  An easy way to check if your aquarium heater is still running is by checking the light while running your aquarium heater.

If your heater has a metal body, you may not be able to see whether the light is on or off. In some cases, the aquarium heater light might not be working, which indicates that your heater may be broken.

The second step checks the temperature of the aquarium: If you’ve checked the light and are still unsure. You can use a thermometer or even your hands to check the temperature inside your tank. If you’re using a thermometer, make sure to put the thermometer in your fish tank before starting the aquarium heater.

After you’ve turned the heater on, let it run for a while and check if there have been any changes in the temperature of the water. Check if your tank is directly facing sunlight because if it is – it might give you an inaccurate reading because the sun might make the tank hotter. Make sure to place your tank in a neutral zone.

A good idea is to always check the temperature with your hands after you are done checking it with the thermometer. Thermometers can sometimes give inaccurate readings.

Wash your hands before putting them into the fish tank. Slowly move your hand toward the heater. If you can feel the heater emitting heat and the water getting hotter as you get closer to the heater, it is working just fine.

If you feel any changes in the temperature during the first step or the second step then your heater works well and not broken.

where to place an aquarium heater?

it depends on the type of the heater, so if you have a submersible heater so it will be under the water and the ideal position is to be right beside the filter output, or if you have a pump you can place it next to it as the warmth of the heater spreads to the rest of the tank through the water.  Install a thermometer in a corner across from the heater to make sure the heat is reaching the other side of the tank. You can position the heater horizontally or vertically but to get the best heat distribution you should mount the heater at a 45-degree angle.

this id if you have a submersible heater but what if you have an internal one ? you can place it in the sidewall of the tank or in corners and this is a common way. if you will install the heater inside the tank be sure to keep it off the gravel because the difference in heat conductivity between the water and substrate could shatter the glass of the heater and make enough space between the heater and gravel or the side of the tank so your fish won’t be stuck against the heater and get burned.


How to tell if the aquarium heater is broken?

this will be a very easy question if your heater contains an indicator led if there is no light then the heater is broken but what if your heater consists of a metal body then you need to check the temperature of the water inside the tank even with your hand or using a thermometer but make sure to measure before you turn off the heater and then after you switch it on and let it for a while to see if there is any difference in the temperature. another way to check is using a bucket or a small tank as a test. fill it with water and then open the heater and after a while check with your hand if the water became warm. With those two ways, you can know if your aquarium heater is working or broken.


in this article, we covered a lot about heaters. why we use a heater inside our tank? what are the different types of heaters that you can use ? and we mentioned that this depends on the type of your tank as if your tank is deep enough then you can use a submersible heater but if it is small then you can use the inline heater. we’ve seen the ideal place for the heater and how this depends on its type, what are the different wattages for the heater and what is the suitable tank size for each one ?. then we mentioned the best aquarium tank heater, what the best titanium heater? and the best digital heater. For those who looking for a 100-watt aquarium heater, we explained the best online 100-watt aquarium heaters with the feature s of each one.

Finally, we ended up by answering five questions that most people always ask, What is the best aquarium heater and size for a 55-gallon aquarium?, how to know if your heater is not working and how to know if it is broken ?, How to install your heater in the aquarium? and Where to place the heater in your aquarium? so this all the knowledge we can provide about the heater and these are the most wanted information about aquarium heaters.
Leave A Reply

Your email address will not be published.