Betta fish heater for 3 gallon tank

Betta fish heater for 3 gallon tank
Find the right betta fish tank heater for your setup

Welcome to my guide to the best betta fish tank heaters. In this guide, you will find information on what constitutes an adequate heater for your betta tank. We warn against products that are specifically branded as betta fish heaters due to their inferior quality. We discuss the different types of heaters providing circumstantial recommendations.

Over the years, I have tried dozens of heaters for my bettas and can think of a select few who I believe are the best on the market.

If youre coming on to this page to find an appropriate and adequate heating unit for the aquarium of your betta fish, then you are in the right place. By the end of this article, you will know how to keep a betta fish warm and cozy.

If youre here to get a quick recommendation, I have listed below the betta fish tank heater. To make a long story short, I like these because they are consistent, accurate, durable, safe, manufactured by reputable brands, and are more adequate for a small aquarium (10 gallons).

If youd like to read all of my ramblings, as I like to call them, then keep reading.

What we typically look for in a heater for betta:

First and foremost, we want our heating unit to be consistent. A heater should precisely and accurately maintain water temperatures at the set temperature at all times.

Certain heaters dont do this and it can be one of the most frustrating of things. An inconsistent heater can be dangerous, especially for a small aquarium. 

To find an adequate heating unit for our bettas aquarium, we need to take a few things into consideration. Usually betta fish are in a 5-gallons tank, which requires less wattage. So instead of paying for a high-wattage heater, were going for a higher quality product.

We want a heater that wont overheat the water, especially since betta aquariums are typically smaller, we need a heater that can operate within a small margin of error.

Now also, Ive also heard of people using good quality heaters and overheating their betta fish because they inserted the heater in a ridiculously small aquarium, like 1 or 2-gallon. Its too small, get an aquarium that is at least 5 gallons.

A bettas aquarium being usually smaller in size we dont want a cheap heater. The margin of error is bigger with a smaller tank, so we want a good quality heater that is reliable.

Durability is very important because dont want to have to buy another one once the cheap one breaks.

Betta fish heater for 3 gallon tank

I cant tell you how many times its happened to me. Over the years, Ive had my fair share of cheap heaters and I dont think theyre worth it. Usually, these heaters stop working after a few months, sometimes longer, but they dont last.

I did that for about two years, while I was in college. Surely, I must have bought the same one 3 times, after which I decided to get something better. I then purchased the Fluval heater and that one ran for 3 years, but then it got replaced with the warranty, which was a great feeling to have.

So durability is definitely a factor to consider.

Betta fish heater for 3 gallon tank
Fully submersible aquarium heater. Image of Fluval E.

In a small-size aquarium, the most efficient heating solution is a submersible heater. Its unlikely that an in-line heater should be required for such a small aquarium. Flat-bed or substrate heaters are notoriously unreliable and dangerous.

When choosing a heater, we have to weigh out the features of each of our choices. For example, we have a display screen, automatic shut-off features, or fish guards. So while we may not absolutely need a display screen, its definitely nice to have.

I definitely like seeing products that come with safety features like automatic shut-offs and fish guards. Especially since were dealing with electricity and water, its always nice to amp on security. 

Usually, if youre going to get electrocuted, itll be because of the heater. And FYI, people who get electrocuted in the fishkeeping hobby can get really hurt. From what I hear, you get a really big shock and have to go to the hospital. So lets be safe folks and turn off the heater before sticking your hand in your bettas aquarium.

Last but not least, adjustability.

Many years ago I purchased a heater online and when it got to my house, I was confused, trying to figure out how to adjust the temperature of the unit. Turns out, its impossible. The heater only heats up to 78-Degree F and thats it. Now, most tropical fish like bettas will be perfectly fine at that temperature.

Betta fish heater for 3 gallon tank
Fluval E

Fluval E 100-Watt Electronic Heater

First up, we have the Fluval 3 100-watt heater, belonging to the mid-price range. 

This particular heater is quite popular in the hobby. What is cool about this heater, is that it has a display screen that shows the temperature of the water at all times. So thats very convenient and helps you get a read of water temperature instantly. 

This is made by Fluval, so thats a brand that has a really good reputation. Personally, Ive really loved all of their products throughout the years. Most of their products, I would say, belong in the mid-range in terms of pricing. But between the low and mid-range, Fluval provides a huge step up in terms of quality. 

The heater comes with a fish guard, so fish and plants wont get burned.

Now obviously, this heater is no good if you have a smaller-sized tank. The length of my 100-watt Fluval E is about 39 centimeters (15 inches). If you dont have enough space vertically, you can use it horizontally. 

Available wattage: 50W, 100W, 200W, and 300W.

Fluval E-Series Heater Operation & Troubleshooting Tips
  • Watts: 100
  • Range: 63 to 93 F
  • Increments: .5

Betta fish heater for 3 gallon tank
EHEIM Jager TruTemp

EHEIM Jäger TruTemp 50W

So next up we have the EHEIM Jäger TruTemp heater which is a 50-watt heating unit that is fully submersible. What I think is the best thing about this as a betta fish tank heater is that it is relatively small compared to other heaters. The length of the thermometer is about 24 centimeters has a very slim appearance.

You can also at the temperatures in increments of .5 this is something that I like because sometimes some heaters dont give you that kind of precision.

EHEIM is just another really great brand thats really popular in the fishkeeping hobby. Id say that the brand is known for its emphasis on precision and accuracy. 

The EHEIM can be recalibrated using their TruTemp technology. So sometimes youll see with some heaters and thermometers, that their temperature readings are not accurate, which is a normal thing as things get older.

Note: When you get it out of the box, just make sure not to move the dial of the heater, or else youll have to recalibrate it. Its so tempting when we get something new to just, play with all the buttons and dials.

The heater is featured with a thermometer safety control which shuts it off when it becomes dry.

  • Watts: 50
  • Range: 62 to 88 F
  • Increments: 1 F

Fluval M-Series

Betta fish heater for 3 gallon tank
Fluval M-series heater

An alternative to the Eheim Jager is the Fluval M-series, which are also built long. The main difference between the two products is that the M-series heater doesnt have a calibration. Both a submersible.

Aqueon Adjustable Pro Aquarium Heater

Betta fish heater for 3 gallon tank
Aqueon Pro

So this is a heater that I have been using and the past few years theyve recently come out with a new 50-watt, Which I think is even better for a Betta Aquarium. The new version is quite small inside when you compare it to other heaters. It has this very slim and mat black finish that I think many betta fish owners will enjoy. 

I find that Aqueon also does well at this price range. For example, this product is part of their higher-end pro product, which Ive come to trust over the years not sure if I would recommend the cheaper products.

Tetra HT Submersible Aquarium Heater

The Tetra HT model is inexpensive and simplistic.

The heater comes at a preset temperature of 78 F. You cannot change temperature settings. Most tropical fish are comfortable at that temperature.

Be wary of the so-called betta fish heaters

These are heaters that are specifically branded as betta fish heaters and address a casual audience within the market. Many manufacturers, like Marina, Top-Fin, and Aqueon provide their own version of this type of product. To be honest, I dont like them. In my experience, I have found these to be unreliable, and grossly inaccurate with the exception of the Marina betta heater.

Betta fish heater for 3 gallon tank
Marina Betta Tank Heater

Marina Betta Tank Heater

I have used the Marina Betta heater for over 4 years now on a 6-gallon betta tank. This is marketed as a betta fish heater, and surprisingly it is a good quality product. In fact, I have never had any issues with this model. However, I would recommend other products in this price range. However, if youre looking for a small heater, then this is perhaps the smallest, yet permissible heater you will find. One good thing about this model is that its very small and compact.

Best Betta Fish Tank Heaters For 5-Gallon tanks:

The list of tiny yet high-quality heaters.

  • EHEIM Jager Thermostat
  • Aqueon Adjustable Pro
  • Fluval E 100

Best Betta fish tank heaters for 3 gallon tank

Since this type of aquarium is really small, Id recommended the Mini-heater by Aqueon. For a 3-gallon tank, its better to choose the 7.5 watts model. Alternatively, the Marina Betta Heater, as mentioned earlier, is of good quality and relatively small.

Best betta fish heaters for 10 gallon + tanks

  • Fluval E 200

Frequently Asked Questions

What temperature do betta fish need?

Between 78 and 80.6° Fahrenheights (or 25 to 27° Celcius).

How to heat a betta tank without a heater

Keep it close to sources of heat and away from cold sources.

So why do betta fish need a heater?

Betta fish heater for 3 gallon tank

Bettas are native to Southeast Asia where the climate is tropical. The adequate water temperature for betta fish ranges between 25 and 28° Celsius. Unless you live in a tropical climate and dont use air conditioning, then you probably dont need one. Its preferable that your aquariums water temperature remains within the range of 25 and 28° Celsius. If temperatures slightly fall below, your fish wont die but itll become highly susceptible to deadly diseases.
Betta fish heater for 3 gallon tank

Monthly temperature ranges in Thailand
Bettas are one of the most popular fish in the fishkeeping hobby but sometimes one of the most misunderstood as well. Over the years, pet stores have grossly misled their customers and dispersed many falsehoods regarding the level of care required by betta fish. This has been heavily criticized primarily, by the fishkeeping community and several animal protection groups.

  • What we typically look for in a heater for betta:
  • Fluval E 100-Watt Electronic Heater
  • EHEIM Jäger TruTemp 50W
  • Fluval M-Series
  • Aqueon Adjustable Pro Aquarium Heater
  • Tetra HT Submersible Aquarium Heater
  • Best Betta Fish Tank Heaters For 5-Gallon tanks:
  • Best Betta fish tank heaters for 3 gallon tank
  • Best betta fish heaters for 10 gallon + tanks
  • Frequently Asked Questions

Do Bettas need heater in 3 gallon tank?

Yes, Betta fish need an aquarium heater to keep the water warm and temperature maintained.

What temperature should a 3 gallon betta tank be?

Betta fish need to be in water that's 78–80 degrees Fahrenheit. How should I maintain the water temperature for betta fish? Use a heater set to keep the tank at 78–80 degrees Fahrenheit.

Can you use a heater in a 3 gallon tank?

You can use a submersible heater. Make sure it has an adjustable thermostat to control temperature. You should also have a thermometer in the tank to monitor water temp.

Is 3 gallons enough for a betta?

Is a 3 Gallon Tank Too Small For A Betta? It is generally agreed that a 3-gallon tank is too small for your betta to be happy in. The tiny tanks used to display and sell betta fish commercially are only for advertising, promotion, and safe transport of the fish.