Best Heater For 5 Gallon Tank Review: Everything You Need To Know

Do you have a 5-gallon tank and are looking for the best heater for it? If so, you’re in the right place! 

This article will discuss everything you need to know about choosing a heater for your 5-gallon tank. 

If you’re going to put together a fish tank, one of the first things you should know is that fish are poikilotherms. It implies they can’t generate or retain body heat, relying instead on the water temperature in which they reside.

That is why you must choose a high-quality heater. Your fish will thrive at the right aquarium temperature, which may be achieved with the right heater.

A freshwater fish tank should be kept between 71 to 86 degrees Fahrenheit; however, some freshwater species demand specific temperatures. For example, if you have betta fish, the temperature should be between 75 and 82 degrees Fahrenheit.

We’ll talk about different types of heaters and what to look for when purchasing one. We’ll also provide a few recommendations for the Best Heater For 5 Gallon Tank on the market today. 

So whether you’re just starting out with a 5-gallon tank or looking to upgrade your current heater, this article is for you!

Related post: Best Fish For 5 Gallon Tank – 15 Fantastic Fish With Pictures (And More)

 Best Heater For 5 Gallon Tank Review

When selecting the right heater for your aquarium, there are so many options that you may feel overwhelmed. Luckily we have narrowed down some of our favorites. The following list includes models from popular brands with good reviews and low failure rates!

Tetra HT Submersible Aquarium Heater


  • Reliable heater for 5-gallon tanks.
  • It is very affordable.
  • Easy-to-use heater for new users.
  • It can be placed vertically or horizontally.


  • There is no adjustable option.
  • There is no dry run protection feature.

Sometimes, heating your aquarium ideally can be a daunting task.

Tetra has the perfect solution – the HT Submersible Aquarium Heater. This heater is easy to use and automatically maintains water at 78 degrees, making it ideal for most tropical fish.

The Tetra HT Submersible Aquarium Heater is the most loved submersible aquarium heater globally. It’s packed with features that make everyday life easier, more entertaining, and more productive. It’s the perfect device for anyone who wants to do more with their aquarium.

With this reliable and efficient heater, you’ll never have to worry about your fish again. It’s perfect for aquariums between 2 and 10 gallons in size, so you can find the ideal fit for your 5-gallon tank.

Tetra HT Submersible Aquarium Heater With...
  • All Tetra HT heaters have indicator lights to let you know when the heater is on. It will be red when heating and green...
  • The HT10 uses a built in electronic theromstat to automatically maintain water at 78° F which is ideal for most...
  • Ideal for aquariums between 2 to 10 gallons with hoods or glass canopies
  • The HT heater is fully submersbile and can be installed vertically or horizontally. It's small footprint makes it easy...
  • Please read all label information upon delivery. DO NOT plug heater into an electrical outlet until it is placed inside...

Eheim Jager Aquarium Thermostat Heater


  • Easy on the wallet – inexpensive.
  • Indicator lights show heater status.
  • It can maintain a steady temperature.
  • It has a built-in dry run sensor to protect dry run.


  • Large size makes placement a bit tricky in 5-gallon tanks.
  • Calibration can be a bit difficult for beginners.

The Eheim Jager Aquarium Thermostat Heater is fully submersible and has a TruTemp dial to recalibrate the heater for precise temperature regulation.

It also features a shock-resistant and shatter-proof glass design for fresh and marine water tanks. Plus, it has an On/Off indicator light, so you can easily monitor its status at all times.

Keep your fish happy and healthy with the Eheim Jager Aquarium Thermostat Heater. This reliable heater will keep your tank at the perfect temperature without any danger of running dry or overheating.

It also comes with mounting brackets, allowing you to position it wherever you choose. Furthermore, they can cling firmly without the fear of falling or slipping on flat surfaces due to gravity!

EHEIM Jager Aquarium Thermostat Heater 25W
  • Fully submersible
  • Thermo safey control protects against running dry
  • Will automatically turn off when water level dips too low
  • TruTemp dial recalibrates the heater for precise temperature regulation
  • Made of shock resistant and shatter proof glass for fresh or marine water

Cobalt Aquatics Neo-Therm Pro Aquarium Heaters


  • Made of Titanium, so very much durable.
  • It contains a separate temperature controller.
  • Extensive heating range (32 to 104°F).
  • Ensures automatic on/off.
  • Ideal for all setups.


  • Suction cups are not very strong.

The Neo-Therm Pro is the perfect choice for your 5-gallon tank. It’s designed to be fully submersible and has an ultra-flat design that looks great in any setup.

Plus, it comes with a reversible holster/bracket, so you can choose to have it face inward or outward. You won’t find another heater like this on the market today!

With just one touch, you can set your desired temperature between 66°F and 96°F, and the Neo-Therm Pro will maintain your tank within 0.5 degrees of its setpoint – no matter what!

The Neo-Therm is concerned about your fish’s safety! So when the heater is going to overheat, the integrated protection circuitry will shut it off, ensuring that no unintended incidents occur.

The cobalt aquatics heater is built of a long-lasting resin that will outlast its glass equivalents. As a result, it’s excellent for individuals who want their aquarium heating equipment to pay off over time!

Cobalt Aquatics Neo-Therm Aquarium Heater (25w),...
  • Super-flat design. Fully submersible, modern design for energy efficient Aquarium and terrarium heating. Includes...
  • Accurate, one-touch system. Simply set temperature between 66-96°f with one touch and the neo-therm electronic...
  • Ultimate safety and reliability. Integrated thermal protection circuitry prevents heater from overheating. If you forget...
  • Virtually indestructible. Unlike cheap, glass heaters, the neo-therm is a resin/thermoplastic heater with a shatterproof...
  • Manufacturer You can trust. Most manufacturers rate their heaters on the ability to raise an aquarium 2-3°f above...

Hydor Submersible Glass Aquarium Heater


  • Convenient for Betta fish tanks.
  • Very effortless to use.
  • Shock-resistant and shatter-proof.
  • Can be positioned vertical, horizontal if wholly submerged.


  • Not very suitable for freezing winters.

The Hydor Submersible Glass Aquarium Heater is the perfect solution to your temperature control needs. It’s submersible, ensuring that your fish are always at their ideal temperature. With this product, you won’t have to worry about them getting too cold or too hot!

The glass construction makes this heater extraordinarily durable and resistant to breakage from impacts. In addition, there is no possibility of thermal shock because the glass doesn’t expand or contract when heated or cooled – which means you don’t have to worry about cracking like other heaters on the market today!

It also features an adjustable thermostat and graduated scale for easy reading and precise maintenance of set temperatures.

Hydor Theo Shatterproof Aquarium Heater, 25-Watt &...
  • Hydor Theo 25-Watt Aquarium Heater is a fully submersible; shatter-proof glass aquarium heater ideal for 2-to-7-gallon...
  • Maximum Safety Aquarium Heater; THEO fish tank heater is shock resistant thanks to the patented PTC heating element and...
  • Free positioning in aquarium with supplied suction cups; The Theo aquarium heater can be placed in the fish tank...
  • Self-Control Limiting Technology; If heater senses abnormal functioning patented PTC heating system guarantees...
  • Great Fish Tank Heater for All Fish Tanks; Universal aquarium heater for use in fresh water or marine water fish tanks

FEDOUR Adjustable Aquarium Heater


  • It is made with explosion-proof glass.
  • Very effortless to use.
  • Dual unit temperature display.
  • A protective cover and collision-proof design are safer for humans and pets.


  • Temperature adjustment is not so precise.

The FEDOUR aquarium heater is perfect for keeping your fish tank at a comfortable temperature, even in the coldest months. With two layers of protection, this heater is safe and reliable.

You can keep your fish happy and healthy all winter long with a FEDOUR aquarium heater.

Fedour aquarium heater is perfect for both fresh and marine water. It is also suitable for all kinds of fish, turtles, and plants.

With a size of 7.5 inches (19 cm), it can be used in tanks with 5-10 Gallons capacity.

You will never have to worry about the temperature of your fish tank again with this adjustable aquarium heater.

The high-precision temperature control system ensures that the temperature stays within the desired range. In addition, the manufacturers offer a 12-month warranty on the whole heater if you have any problems.

FEDOUR Adjustable Aquarium Heater with Protective...
562 Reviews
FEDOUR Adjustable Aquarium Heater with Protective...
  • 【More Power and Longer Life】This heater is for 5-10 gallon fish tank, comparing to 25W, this 30W aquarium heater is...
  • 【Double Safety Protection】2mm thickened explosion-proof glass, 33% thicker than normal 1.5mm aquarium heaters,...
  • 【Application】30W suitable for 5-10Gallon fish tank, suitable for both fresh and marine water, suitable for all kinds...
  • 【Adjustable】High-precision temperature control system, adjustable temperature ranges from 68°F to 93°F(20°C -...
  • 【Complete accessories】An additional stick-on thermometer as a bonus to detect water temp at any time, and 3pcs...

Penn-Plax Aquarium Heater


  • Firm suction cups.
  • Easy-to-read Celsius / Fahrenheit setting scale.
  • The after-sale service is satisfactory. 
  • It can be placed horizontally or vertically.
  • It comes with a 3-years warranty.


  • It doesn’t show the current water temperature.

This Penn-Plax aquarium heater is fully submersible and has a digital thermostat to ensure your desired temperature is always reached. So, you’ll never have to worry about your fish again with this reliable aquarium heater.

It comes with two suction cups for easy and secure placement, so you can rest assured knowing your aquatic pets are always comfortable. With its heavy-duty shock-resistant glass, this aquarium heater will last you for years to come.

It sets and maintains the temperature in your tank within 1-degree accuracy, has both Fahrenheit and Celsius temperature readings, and can be placed horizontally or vertically in your tank.

With this heater, you won’t have to worry about your fish getting too cold or too hot with this heater – it has a preset temperature of 76 degrees Fahrenheit but is also easily programmed to whatever temperature you want.

The heater is safe to use on smaller fish tanks and aquariums up to 5 gallons in size.

Penn-Plax Cascade Heat Aquarium Heater – Fully...
  • FULLY SUBMERSIBLE AQUARIUM HEATER: The 25W Cascade Aquarium Heater easily maintains healthy water temperature within a...
  • VISIBLE & ACCURATE TEMPERATURE SCALE: With an easy to read setting scale in both Celsius and Fahrenheit, it’s easy to...
  • ORANGE PILOT LIGHT: Our Cascade Heat Aquarium Heaters feature a pilot light that indicates the heating cycle status....
  • ADDITIONAL FEATURES: In addition to being composed of heavy-duty and shock-resistant glass, these fully submersible...
  • MEASUREMENTS: Overall Length = 7.5” / Overall Diameter = 1.1” / Suction Cup Diameter = 1.25” / Wattage = 25W /...

FREESEA Aquarium Heater


  • Compact to fit any shape of the tank.
  • Automatic turn on/off feature.
  • Easy to use and install.
  • The after-sale service is good. 


  • The power cord is very short.

A decent heating system for a 1 to 10-gallon fish tank is the FreeSea Aquarium Heater. Even though there are larger options that will assist larger tanks.

This is a small but essential heater that we all require. The FreeSea Aquarium Heater is an excellent option for warming 5-gallon aquariums to temperatures ranging from 59 to 94 degrees Fahrenheit.

It includes built-in dual safety protection, which is great because it protects against overheating. 

The FreeSea Aquarium Heater is a programmable temperature controller that can keep your aquarium at the right temperature and can start at any moment when the temperature falls below the specified point.

There’s nothing left to do but plug this thing in and set your desired setting with the help of an easy-to-read digital display panel on top.

FREESEA 25 Watt Aquarium Betta Fish Tank Heater...
  • ★【25 Watt Heater】: This Aquarium heater is suitable for 1 to 5 gallons aquariums, Length - 6.8 inch,voltage...
  • ★【Temperature range】: 63°F~95°F , It is very easy to adjust the temperature you need, we also deliberately give...
  • ★【Intelligent temperature control】: Automatic constant temperature function, when water temperature reaches to...
  • ★【Note】: 1. Aquarium heater is 100% submersible use only, during its heating time, heater must be 100% submerged...
  • ★【SATISFACTION GUARANTEED】: Gain the confidence to go hard with us! Our Aquarium Heater is built with durability...

SZELAM Smart Mini Aquarium Heater


  • Easy to install and use.
  • Good material of construction.
  • It consumes minimal energy.
  • Nice and compact design.


  • Sometimes it works slow.

SZELAM Smart Mini Aquarium heater is a totally submersible tiny aquarium heater with 3 adjustable temperature settings. It’s suitable for aquariums from 5 To 20 gallons.

The size of this heater is petite, which may be hidden in the aquarium décor, so it won’t impact your vision.

You can customize the temperature according to your needs or let it auto-adjusting; just let the SZELAM do its thing!

A thermostat is not required with this Smart Mini Fish Tank Heating system. However, unlike some other heaters, a unique thermometer will undoubtedly maintain functioning inside the stated temperature.

The heater is straightforward to install, and also it’s easy to use. In addition, it comes with an instruction booklet that will undoubtedly guide you in setting it up quickly.

One of the unique elements of the heating system is that it is created from high-grade material. So it is a powerful, functional, and generally top-quality 5-gallon tank heater.

SZELAM 25W Smart Mini Aquarium Heater, Betta Fish...
  • Smart Control- Adopted intelligent circuit board, with a precise temperature sensing probe and constant temperature...
  • Easier to Use- SZELAM Mini Heater different from a manually adjusted heater. Our heater automatic temperature regulate...
  • High Quality- Made by heat resistant ABS housing, sandy quartz filler and MCH Alumina ceramic heating system, anti...
  • Mini Sized- Fully submersible compact betta fish heater Gift with 2PCS Aquarium Decor Artificial Plant. Specific perfect...
  • Quality Assurance- This product have certificated by CE, ROHS, FCC certifications. We will provide replacement items for...

How to Choose the Best Heater For 5 Gallon Tank: A Buyer’s Guide

Because of technological improvements, there are a plethora of high-quality heaters on the market. However, some types will always stand out from the crowd. Some of the considerations to consider while purchasing a heater are listed below.

Best Heater For 5 Gallon Tank - Buyer Guide

Tank Size And Wattage

The heater must supply enough power to heat the water in the tank properly and consistently. When selecting a tank heater, consider the volume of water, the desired temperature, and the average room temperature.

In general, for a single gallon of water, we recommend using between 2.5 and 5 watts. As a result, if your tank holds 5 gallons, your heater should be able to provide between 12,5 and 25 watts. 

If one heater isn’t enough, you can always get two.


You should also look for a heater that has a precise thermostat. The thermostat’s job is to keep your pet’s home at the desired temperature. 

It has a sensor that continuously monitors the water’s condition inside the tank. Ensure the thermostat is always accurate to avoid unwanted water temperature levels (below or above the ideal range).

Temperature Control

You will have two options for purchasing a heater for your tank. You can buy one with a preset temperature or one that allows you to modify the temperature.

The option that allows you to modify the temperature as desired is the best of the two options. The main reason is that outside temperatures might vary, affecting the temperature inside the tank.

For example, if it’s bitterly cold outside, you’ll need to alter the temperature in the tank to keep the fish comfortable. On the other hand, if it is extremely hot outside, you can modify the temperature in the tank to ensure that the fish are not uncomfortable.

Clarity And Readability

The primary reason for purchasing an aquarium heater is to be able to heat the water and monitor the temperature. As a result, you must buy a heater that is clearly readable.

Setting the correct temperature and monitoring temperature swings becomes easier in this manner. If you want to keep the water in your tank warm enough for your fish, the heater you choose must also deliver accurate readings.

Safety Functions

A water tank heater is often installed within the tank and consumes a significant amount of electricity. However, most heaters are safe because they contain an automatic safety shut-off feature that turns the controller off if it is not entirely submerged in water.

As a result, the safest option for your fish and you is to purchase a heater with a shut-off feature. Make sure the heater you are buying has the highest level of safety features.

Always Use A Thermometer Inside The Tank

Whatever type of heater you choose, you must keep an eye on the water temperature at all times. 

Stick-on thermometers attached to the tank’s outside measure the ambient room temperature rather than the water temperature, which can be very different. 

Use a glass thermometer with a suction cup to mount to the inside of the glass for the most accurate water temperatures!

Final Thoughts

The best way to keep your fish happy and healthy is by making sure they have the right equipment. Unfortunately, heaters are an overlooked aspect of this, given how low or high temperatures can affect them drastically.

You may not think heaters are important for your tank, but they can make or break it.

So, we have done all of the hard work for you and narrowed down our top picks above. All that’s left is for you to read through them and decide which one suits your needs best!

If you have anything more to know, please leave a comment below!

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