The Ultimate Guide to Best Heater for Betta Fish Tank

Betta, being a tropical fish, feels comfortable in a warmer environment. So, do betta fish need a heater?

Yes, they do!

A betta fish prefers living in temperature ranging from 78°F to 80°F (25.5°C to 26.5°C). If the temperature starts to drop below 72°F (22°C) or rise above 86°F (30°C), their lives can hang by a thread!

Moreover, room temperature tends to change throughout the day. So, they have to adjust their body temperature constantly with the changing room temperature.

The obvious solution is getting the best heater for betta fish tank.

An ideal product will not only offer better heating but also prevents temperature fluctuations despite external conditions.

Every single company in the market claims to be the best heater for betta. A lot of people even get victimized by the glory and gleam of the advertisements and end up getting a crappy product.

Don’t worry as I would talk about (and rank) some of the best in this article, along with some critical buying considerations.

Product Name

Heat Range

Power (Watt)



​Cobalt Aquatics Flat Neo-Therm Heater​66-96°F​25W-300W
​Tetra HT​78°F (Preset)​50W-200W
​Hygger Submersible Aquarium Heater​75-91°F​50W-300W
Fluval M Submersible Heater​66-86°F​50W-200W
​Fluval Marina Submersible Heater for Aquarium, Mini​Not specified​25W-50W

5 Best Heaters for Betta Fish You Can Get Your Hands On!

The Polish brand, Cobalt Aquatics, has designed a superior product that offers extensive functionality and robustness. The first thing that you would notice is the flat design that gives it an aesthetic and modern look.

  • – It looks Not only modern, but it also has advanced features. It comes with a one-touch control system that can set the temperature from 66°F to 96°F. So, it can easily maintain the ideal temperature for a betta tank.
  • – You might not know, but not all the heaters can maintain a constant temperature. So, there is always a gap between the set temperature and the actual temperature. This product always keeps the actual temperature within ±0.5°F compared to the set temperature.
  • – It can increase a tank temperature up to 11°F higher than the room temperature, whereas a cheap product can barely cross the 2-3°F mark.
  • – This fully-submersible heater comes with integrated thermal protection technology. It will prevent the heater from overheating as well as enable automatic shutdown if you forget to press the off switch.
  • – The build quality is much, much superior as the outer shell is made of thermoplastics rather than a typical glass body. So, you can call it genuinely shatterproof.
  • – ​Finally, you will get an abundance of options. There are nine variants of the same product with watt count ranging from 25W to 300W suitable for 6 gallons to 125 gallons tank capacity.


  • ​Has an appealing super-flat design
  • ​Easier operation with the One-touch Control
  • ​Consistent at maintaining temperature
  • ​Safe; prevents overheating and has automatic shutdown feature
  • ​Robust build quality
  • ​Has a LED panel to indicate the set and actual temperature
  • ​Comes in nine variants


  • ​Some buyers complain about inconsistent performance
  • ​Efficiency drops in stagnant waters

2. Tetra HT Submersible Aquarium Heater – The Budget Heater for Betta

It is the perfect heater for budget-conscious buyers. A lot of people assume that a cheaper option is undoubtedly a bad option, that’s not true for every scenario!

  • – The whole concept of this heater from Tetra is to hit all the essential features and to cut off the dazzling add-ons. Rather than having an LED panel, it has a red-green indicator. The light turns green when it reaches the desired temperature.
  • – You can’t adjust the temperature with this heater! It’s thermostat always achieves 78°F temperature and maintains it. As most of the tropical fishes, including bettas, prefer living at 78°F, it should be perfect for you.
  • -Tetra HT is a 50W heater designed for smaller aquariums (2 to 10 gallons). So, you should only consider this one if you are not planning to use it in a large tank.
  • -​ Most Tetra submersible heater review suggests that it is a fully submersible heater that you can place either horizontally or vertically.

Yes, it doesn’t have many features, but it will get things done!


  • ​Budget-friendly, one of the cheapest in the market
  • ​Minimalistic design
  • ​Fully submersible
  • ​Compact size and easier installation


  • ​Can’t change the 78°F default temperature
  • ​Need a hood or glass canopy; otherwise, it underheats and eventually malfunctions
  • ​Build quality is average
  • 3. Hygger Submersible Aquarium Heater – Best Bang for the Buck! 

If you are into the fish and aquarium topics, you must have heard about Hygger. This Chinese brand is one of the biggest names in this market all over the world.

  • – The worst nightmare of a fish keeper is the thought of an exploding heater! This Hygger heater uses heat resistant milky quartz material that can sustain even 1800°F temperature.
  • – ​​You will not have to continually check the thermometer to make sure it’s not over or underheating. It has smart temperature adjustment technology.
  • ​If the water temperature goes 1.5-2°F above the preset temperature, it stops heating. On the other hand, if the temperature drops 1.5-2°F below the preset temperature, it starts heating again.
  • – ​It also comes with an overheat protection technology. If the water temperature exceeds 97°F, it shuts down. Moreover, a secondary circuit takes control so that the same issue doesn’t occur again. Still, 97°F is a very high temperature for betta, and you should be concerned about this.
  • – ​Rather than a button or touch-control mechanism, Hygger has chosen to go with a dialer-based control system. You can select any temperature from 75-91°F. There is an LED indicator that tells you if it is actively heating or not.
  • ​There are three heater variations available (50W, 100W, and 300W) based on heater length and power (Watt count) that are suitable for 7-gallon to 60-gallon tanks.


  • ​Explosion and shatterproof design
  • ​Heat resistant filament material
  • ​Temperature adjustment technology
  • ​Overheat protection and automatic shutdown mechanism
  • ​LED indicator
  • ​Three variations available


  • ​Has to be set horizontally to work properly
  • ​Some buyers have reported occurrences of malfunctions

4. Fluval M Submersible Heater – Easiest to Carry

Fluval M takes a different approach compared to its competitors in terms of design aesthetics, at least. Most of the other brands are trying their hard to make the product better looking.

  • – They, on the other hand, have applied reflective technology to make the heater blend with the aquarium environment.
  • – Also, they are using shock-proof Borosilicate glass as the building material. You can even see high-density ceramic heat sinks to stop it from overheating.
  • – ​You will be getting some of the premium features too, like – automatic shutdown, LED indicator, dual temperature sensors, etc.
  • ​Currently, there are four variants of the product – 50W, 100W, 150W, and 200W.

Overall, it’s a decent quality heater that you can consider buying mainly because of the brand value.


  • ​Adjustable temperature control
  • ​Fairly durable
  • ​Reflective technology
  • ​Shock-proof design with ceramic heat sinks
  • ​Dual temperature sensors
  • ​Four variations available


  • ​Has a high price-to-value ratio
  • ​Customers have reported some cases of overheating

​5. Fluval Marina Submersible Heater for Aquarium, Mini – Easy to Use

If you have liked the Tetra HT in the second position, you are going to love Fluval Marina – they both follow the same design principals. These smaller heaters are often called mini heaters, and they are so popular among the fish keepers these days!

  • There are two options available – 25W and 50W that can handle 5.5 to 10 gallons at best.
  • – ​Unlike the Tetra HT, you can set the temperature using the dial on top of the heater body. However, it can reach 78°F at max! Still, people often call it the best betta heater.
  • – ​You can call it quite safe as it has a waterproof seal and ceramic core. Moreover, the ceramic core is surrounded by a glass shield.
  • ​The installation process is like a cakewalk. There are brackets with suction cups that you can attach in the inner wall of the aquarium.


  • ​Small yet effective
  • ​Has a dial for adjusting the temperature
  • ​Has two available variants
  • ​Safer design
  • ​Budget-friendly


  • ​Requires an additional thermometer
  • ​Can reach 78°F at best

The Ultimate Buying Guide to Choose the Best Heater for Betta Fish

There several factors that you should consider while choosing a heater for betta. Check them out

Heater Wattage vs. Tank Volume

Almost all the heater manufacturers create more than one variant of the same model.


You can’t use the same heater in every tank expect it to work like a charm!

It’s mandatory to ensure consistency and even heating throughout the tank.

That leads to the main question – what should be the ideal wattage of the heater based on the tank size or capacity?

The minimumwattage to gallons of water ratio is 3:1. For a better result, you should use a 5:1 ratio.

That means you will need at least a 30W heater to heat a 10-gallon fish tank properly. However, it’s better to be on the safe side. So, I would suggest you go for the 5:1 wattage to gallons of water ratio.

You can even use multiple numbers of smaller heaters to achieve a proper overall wattage.

For example, you can use three 30W heaters instead of one 90W heater for a 30-gallon water tank.

More: Read our guide to Bestt Betta Tank here

Adjustable vs. Preset Heaters

Some heaters don’t have the option of adjusting the temperature; instead, it always operates at one preset level.

This is more common among the smaller and cheaper heaters in the market. In most cases, the preset temperature is 78°F as most of the tropical fishes, like betta find this temperature comfortable. Tetra HT in the listing above falls into this category.

I would suggest you go for the adjustable ones so that you can have better control over the process.

But, here’s the catch, they cost more!

So, it’s a trade-off between value and functionality.

The final decision is up to you.

More: Read our guide to best plants for betta tank here

Hey, What’s the Temperature?!

As bettas are very sensitive to the temperature, you should always keep an eye on the temperature of the water.

A better heater will have two temperature indicators – one indicates the desired temperature; another indicates the actual temperature.

Such functionality might hurt your wallet a bit, as they are pricey. But it’s worth the cost.

However, you shouldn’t blindly trust the readings as they could be inaccurate. It might show that the actual temperature is 78°F, while in reality, it could be 88°F.

You should always double-check the readings and keep a spare thermometer.

More: Read our guide to best substrate for betta tank here

Ease of Use

An aquarium heater shouldn’t feel like handling a gadget from Star Wars!

Don’t the wrong idea; I am not saying that the heater shouldn’t have features or additional functionality. Simplicity is the key. It should be easy, natural, and obvious.

For example, if the heater has large knobs to set the temperature, it’s easy.

There are a lot of smaller details that make a heater easier or harder to handle.

Is It Safe?

The first thing you should look for is whether the heater can explode or not. Make sure the heater is entirely waterproof, otherwise it can lead to nasty accidents.

Some of the heaters require to be fully submerged underwater to operate properly. Leaving it partially submerged can cause malfunctions.

You should avoid the partially submersible heaters altogether. They are not worth the risk!

Then, check if a heater has an automatic shutdown feature or not. It will prevent your bettas from boiling!

Other design ideologies like being shatterproof, shock-proof, waterproof, etc. are great things to have.

More: Read our guide to different type of betta he​​re

What Is Your Typical Room Temperature?

When buying a heater, you should check the typical room temperature first. If you live in a colder area, you will need to buy a powerful heater that can increase the tank temperature to a desirable level.

For example, if you live in an area where typical room temperature falls to 60°F occasionally, you need a powerful heater that can increase it to at least 75°F.

On the other hand, if your room temperature never falls below 75°F, you don’t need to spend a fortune on buying a heater.

What Type Is It?

There are a lot of choices available for you as manufacturers are designing different types of heaters to meet the varying customer demands.

Here are the popular options –

  • 1. Immersible or Hanging Heaters

As the name suggests, these heaters hang from the top of the fish tanks. Only the heating core remains submerged under the water. This is the most basic design and the oldest one too.

To install these, you will need to create an opening in the tank hood.

However, you should probably avoid owning an immersible heater as they are prone to danger. You can even electrocute your fishes!

  • 2. Submersible Heaters

Compared to the immersible heaters, they are modern. Rather than dipping the heating core into the water, you can submerge the entire unit in water.

You can put it in the water as long as it doesn’t touch the gravel beneath the water or the side walls. If it touches the sidewall, the heat dissipating from the heater might cause cracks.

Among all the types, I prefer having this one for my fish tank.

Just make sure to get a fully-submersible one, and not a partially-submersible one. It offers better safety.

  • 3. In-filter Heaters

You are probably getting a filter, too, for creating a cleaner environment for your betta. If you are not considering it yet, you should!

Some of the filters have built-in heaters. You can call such devices a filter-cum-heater. So, basically, we call such heaters an in-filter heater.

The idea is very convenient, but there’s a catch!

In most cases, the in-filter heaters tend to be quite mediocre, made of cheap materials, and have poor build quality.

If you are determined to get an in-filter heater, make sure that it can maintain the water temperature at your preferable level.

  • 4. In-Sump Heaters

A sump is a separate compartment underneath the main tank for storing water heaters, food supplying kits, water filters, etc. Basically, it keeps the tank accessories out sight to give a cleaner look.

An in-sump heater is built-within the sump. Again, it brings convenience.

  • 5. In-Line Heaters

An in-line heater doesn’t reside within the sump or the filter, rather fitted in the line between a sump or a filter and the main tank.

You can mostly see an in-line heater in the larger tanks. They are quite effective and safe, but the whole setup costs a slot of money.


What Water Temperature Range Is Best for Betta Fish?

  • The ideal temperature ranges from 78°F to 80°F (25.5°C to 26.5°C).

How to Add a Heater to a Betta Tank?

  • – Once you get the best heater for betta tank, first check if it is a tip-top condition. Check for possible crack or transportation damages.
  • – ​Then, find a suitable place to locate the heater in the tank. You should follow the installation guide recommended by the manufacturers – i.e. using suction caps or installing mounting brackets.
  • – Only after installing it properly, power it up. Now, monitor the water temperature using a separate thermometer. You should keep an eye on the water temperature for at least 24 hours.
  • ​If it remains stable, let your betta enjoy its new home.

How to Use Betta Fish Heater?

  • – Start by adjusting the dial (other temperature input) to 78°F and place the heater in the water. After about 15 minutes, power up the heater. Wait another hour to reach a stable temperature. Now, have your pet betta in a plastic cup filled with water of ambient temperature. Float the cup on the tank water surface.
  • ​- After the two temperatures of the cup and the tank syncs together, put the betta into the water.


Creating a suitable home for your pet betta will ensure healthy growth. You should choose your preferred heater, depending on your situation. Not every model is suitable for everyone.

Still, the Cobalt Aquatics Flat Neo-Therm Heater clearly stands on top of the list as it has every single desirable feature that you can imagine.

Tetra HT claims the second spot being the best budget heater in the market. Hygger Submersible Aquarium Heater follows it in the third-place, being the value champ!

If you are in short of budget, wait till you can save up for the best heater for betta. Remember, it’s an investment that can make your beloved pet happy and thriving!


  • William Rieder

    Hi, my name is William Rieder and I'm a pet and animal blogger. I love reviewing all things pet related, from dogs to cats to horses! I also write about other topics such as personal finance and relationships. I enjoy helping people find the perfect pet for their lifestyle and am always interested in hearing what they have to say about their pets.

Leave a Comment

Your email address will not be published. Required fields are marked *