Do Betta Fish Need A Filter And Heater

Do Betta Fish Need a Filter in a 5-Gallon Tank?

Do Betta Fish Need A Filter And Heater7 mins read

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Do Betta Fish Need A Filter And Heater

The elegant and bold-colored Siamese fish drifting in a tiny bowl is a common site, but do betta fish need a filter? These setups sadly often come with no filtration or heating system, maybe a few plants and decorations, but not much more than that. As you may have seen in many pet stores, even on television and in magazines, this is common. However, it’s not ideal for betta fish.

I cannot be more candid, this practice is completely cruel and not at all the way any tropical fish, especially a Betta fish should be kept. So if you are wondering ‘do betta fish need filters?’ the answer is a resounding YES, and this article will explain why.

Yes, some sources state that they can survive in low-oxygen environments and small puddles in the wild, they are labyrinth fish and can gulp air from the surface when they need it. These are facts in severe cases in the wild, where they need to survive because they do not have any other means, however in captivity you should provide your fish with a proper aquarium.

The difference is do you want your fish to survive and be miserable, or thrive and be content?

This article will answer whether betta fish need a filter and ‘do betta fish need a heater’ plus more explanations. In short, depending on the climate where you live, you may need a heater. And unless you want to clean your tank every other day, you will need a filter. It will also look into betta fish general care to explain why they have such sensitive needs, so read on.

Do Betta Fish Need Filters And Heaters?

Do betta fish need filters and heaters?
Filters circulate the water in your tank causing aeration, which provides more oxygen for your fish to thrive. Image from Wikimedia

By now, it’s clear that your Betta fish do need a filter and a heater. In very rare cases and conditions you may be able to go without a heater, but a filter will be more tricky. So let’s look at it, and why you may need a heater or filter for your betta fish.

Do Betta Fish Need Filters?

The answer is YES, most, unless you would like to clean the entire tank every day and replace the water with properly conditioned water. A practice that will cause stress for your fish, and much frustration for you. Here are a few reasons why you need a filter:

  • The filter removes particles from the water and supplies the substrate with beneficial bacteria to help process fish waste. The Beneficial bacteria convert ammonia from fish waste to nitrites and then nitrates which are a much safer compound. The build-up of ammonia and nitrites cause the most health concerns in fish.
  • Filters circulate the water in your tank causing aeration, which provides more oxygen for your fish to thrive. Though Bettas are labyrinth fish that can live in low oxygen levels, they should not have to and should be able to enjoy their aquarium.

Compare yourself to being placed in an airtight box, with only a tiny hole for oxygen, and having to live in your own waste, the case is similar for any fish in an aquarium without a filter.

Best Types Of Filters For Betta Fish

Because betta fish are slow swimmers. Therefore, they need a filter that does not have a strong current, which could make it difficult for them to swim, or even stay stationary. Thus Internal filters, or back-hanging filters are the best choice for betta fish. Sponge filters are also an excellent choice. So, ‘do betta fish need a filter’ is not just a simple yes/no question.

Filter Maintenance

You can clean your filter every few weeks with clean conditioned water. In this process, remove some of the media from your filter and replace it with new media.

Do Betta Fish Need A Heater?

Betta fish are tropical fish, thus they require warmer water temperatures. In some cases, many aquarists use a room heater, or you may live in an area with a very hot climate. Therefore, as long as the temperatures are consistent, you can consider not using a heater. However, the general answer to ‘do betta fish need a heater’ is yes, in the northern hemisphere.

Though Betta fish need consistent temperatures of Between 24-28 degrees Celsius, or (75-82 Fahrenheit), and anything warmer or cooler could be detrimental for your Betta fish. Though Betta fish can live in colder water, it does affect their immune system. Generally, it really will not be comfortable for them.

The Best Types Of Heaters For Betta Fish

The best types of heaters for betta fish are those that you can immerse in the water. Here are a few options in heater types for betta fish:

  • Inline Heaters – In-Line heaters are not immersible but are one of the best outside heaters. Should you choose this type of heater, you will find it still keeps consistent water temperatures.
  • Substrate Heaters – substrate heaters consist of coils or cables that are placed underneath your substrate. These radiate heat from the bottom upwards into the tank.
  • Filter and Heater Combos – many aquarium filters come as a combination including an in-line heater heating and water filtering simultaneously.
  • Other Heating Methods – You can use a room heater in a small enclosed room that heats up to 78 degrees Fahrenheit as another heating method. Sunlight can likewise provide heat, however, it may cause your tank to become dirty quickly. Remember, it can also overheat the water. Likewise, there will be no heat at night. Another method is floating hot water bottles on the surface of the Aquarium, however, this is just a temporary solution.

Things To Note:

All in all, my advice is to save yourself the trouble, and risk of other heating methods, and the electrical bill of a room heater, and invest in a proper tank heater.

 Breed Overview

OriginSouth East Asia originated from Thailand.
LifespanAround 2-5 years.
SizeThey are 6 -8 cm, (2.4-3.2 Inches), rarely reaching more than 3 inches.
ColorsBetta Fish come in Color and Finnage Variations, but mainly red and Blue.
Water pHNeutral pH of 7.0 or higher.
Tank SizeA tank Size of 3 -5 gallons is ideal, however, one-gallon tanks are acceptable for a single Betta.
TemperamentAggressive especially towards other males, relatively social and active, they are also quite intelligent.
Water TypeFresh Colder Water.
Water TemperatureBetween 24-28 degrees Celsius, or (75-82 Fahrenheit)
Difficulty LevelIntermediate to Advanced.

Species Information

Beautiful betta fish
Betta Fish are generally available in bright dark blue or red colors, though you get more color variations, even some rare colors such as the silver and purple Betta.

The betta Fish comes from the anabantoid family, they have a unique labyrinth organ that allows them to breathe air from the atmosphere and underwater. Also called the Siamese fighter, humans originally bred them as fighting fish in Thailand for gambling games.

Today however they have become popular pets for their exquisite color and finnage variations, and their curious, social antics. Betta Fish are generally available in bright dark blue or red colors, though you get more color variations, even some rare colors such as the silver and purple Betta.

Betta fish are labeled as aggressive, and territorial, especially towards other males and females. However, females can be kept together in a group of four or more fish, where they will develop a ranking order or hierarchy. There are a few other fish species that you can keep with your Betta fish, which we will discuss shortly. Remember, the betta’s environment is the key to answering ‘do betta fish need filters?’.

Caring For Betta Fish

Caring for betta fish
The Betta fish needs a tank that is between 3-5 gallons for a single Betta fish, and bigger should you be adding tank mates.

Betta fish have striking intense colors, and entertaining antics which you will enjoy watching. They are eye-catching in any aquarium, however, they do need proper care and water conditions to thrive.

I am going to provide you with a brief guide for caring for your Betta fish, some links will be included in each step should you need more in-depth information from trusted sites.

1. Setting Up Your Aquarium

In short, for a contented and healthy Betta fish, these are your aquarium requirements:

Should you need more comprehensive information Wikihow has an outstanding page that offers step-by-step instructions.

  • Tank Size

The Betta fish needs a tank that is between 3-5 gallons for a single Betta fish, and bigger should you be adding tank mates. You can get away with a 1-gallon tank at least for a single Betta, with more regular maintenance.

  • Water Conditions

Betta Fish require cooler water conditions of 24 – 28 degrees Celsius (75 – 82 Degrees Fahrenheit), which is pH neutral, to more alkaline pH 7.0 or more, and soft water. They can survive in low oxygen levels and colder water. However, it will affect their immune system and eventually their health.

  • Substrate

With thorough research and experience I have found that gravel and sand are the best substrates. They are the easiest to keep clean and safest in terms of collecting debris and waste. A darker shade of gravel will highlight the attractive colors of your betta fish.

  • Lighting

Betta fish do need a clear indication of day and night, but should not be kept in direct sunlight. Instead, keep them in an area with indirect or dappled light. You can similarly invest in a tank light that you can switch on and off.

  • Decorations

Tank decorations create much-needed hiding spaces which Betta fish enjoy. This is as they are territorial creatures and they do need enrichment. Driftwood, Rocks, caves, and Castles that have smooth edges and no sharp protrusions are ideal.

  • Plants

You can invest in both live or synthetic silk-type plants for your Bettas, though I recommend Live plants as they help to clean your tank and oxygenate the water. Also, use floating plants as male Betta fish create bubble nests.

Feeding for betta fish

You can invest in both live or synthetic silk-type plants for your Bettas. Image from Flickr

2. Choosing A Betta Fish And Adding The Fish To The Tank

You can get good quality and healthy Betta fish from a Trusted breeder or pet store. It is important to select a juvenile or young fish, rather than an old or baby fish.

A Healthy Betta Fish will be active and alert, with bright coloring and no brown patches, or white spots near the gills or on the fins. The eyes will be clear and black, and the fins will have no damage to them. Likewise, check the tank conditions and other fish. The water should be clear, and other fish in similarly good condition.

3. Selecting Tank Mates

If you wish you can select a few different fish species companions to cohabitate with your Betta fish. They may even be welcomed and provide good exercise for your betta chasing them around. Just make sure to add the tank mates before your Betta fish.

Select fish that are fast swimmers and tend to shoal, that do not have long tails and fins. They should also not be brightly colored. Bettas will nip at fish with long fins. Try to avoid larger and more aggressive breeds of fish. A few species to consider are

  • Tetras – Small and fast.
  • Loaches – Bottom feeders to clean your tank.
  • Malaysian Trumpet Snails – Snails help to clean the tank.
  • Corydoras – Catfish breed and bottom feeder.
  • Rasboras – Colorful, fast, and peaceful.
  • Danios – Peaceful and fast.

Breeding and Feeding are beyond the scope of this article. However, remember that if you want your betta fish to mate, dirty water is a big NO. Therefore, for ‘do betta fish need filters’, the answer is a big YES especially if you want to breed them! I recommend that you read about breeding from our more comprehensive page on the subject;  “How to Do Betta Fish Mate”. 

Breeding for betta fish
Remember that if you want your betta fish to mate, dirty water is a big NO Image from Flickr

4. Maintaining Your Tank

Maintaining your tank becomes exceptionally difficult if you do not have a filter system. You will have to clean out the entire tank daily, though if you have a filter it is important to do a weekly water change, by removing at least 20 -30 % of the tank water from the bottom with suction and replacing it with the same amount of new conditioned water. You should clean plants and décor when you need, and remove waste from dead plants.

Common Health Issues

My betta fish is not eating food
Betta fish need a spotless tank with optimal water conditions, and a good diet to stay healthy and thrive.

Betta fish need a spotless tank with optimal water conditions, and a good diet to stay healthy and thrive. A few main conditions that ail Betta fish include;

  • Ich – A parasite causing White spots on the gills and fins of the fish.
  • Velvet Disease – An infection causing a gold-brownish coloration of your fish.
  • Fin Rot – A bacterial infection that spreads from the fins to the body.
  • Dropsy – Causing Bloating because of a compromised immune system.
  • Physical Damage – From handling, bites from other fish, or injuries from tank decorations.

Almost all these conditions are either caused, or aggravated by poor water quality, and dirty tanks. This is a major reason why betta fish need a filter, regardless of where you are in the world!

In all these cases the fish will need to be quarantined in a tank with optimal water conditions, and medication such as antibiotics and water conditioners can be added. However, in our article “Betta Fish Behaviour Before Death” you can read more about health issues and diseases.

To Conclude

How long can betta fish live without a filter
The tank size is also important, as even if they are happy to be kept on their own, they still need ample space, and tank décor and plants to keep them occupied. Image from Flickr

Betta fish are commonly kept as pets, they have absolutely striking color varieties and are quite intelligent and social fish that love to interact with their humans. If you want to keep your Betta fish healthy, happy, and thriving, I do urge that you rather invest in a proper heater and tank filter, than try to go without the latter.

The tank size is also important, as even if they are happy to be kept on their own, they still need ample space, and tank décor and plants to keep them occupied. If you are still set on having an aquarium without a heater or filter for your Betta fish, you can always consider a Self Sustaining Ecosystem, which is much more effort initially, but very rewarding if done correctly.

Frequently Asked Questions

Are Sponge Filters a Good Choice for Betta Fish?
Yes, Sponge filters are essentially one of the best types of filters for Betta Fish. The Sponge Filter uses a sponge and air pump that draws the water through the porous sponge to filter the tank. It is small and has a relatively light current which is perfect for the slow-moving Betta fish.
How Long Can Betta Fish Live Without a Filter?
There is much controversy around this topic, however, to be on the safe side the maximum is 7 days without a filter, provided that you clean the water daily. Living in an unfiltered tank will affect the health and immune system of your fish, though they may survive, they are not thriving or happy in a dirty tank.
Do Betta Fish Need a Filter in a 5-Gallon Tank?
You may have read that aquariums that are 5 gallons and more are safe to go unfiltered for a Betta fish if there are enough live plants producing oxygen, and little or no other fish species except maybe for snails to clean the tank. Then again more frequent and substantial water changes will have to be done similarly. Though, I will still rather opt for a filter, as this may not work out as well as planned, and 5 gallons is still too small to go without a filter.
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Tal Halperin

Tal is an avid fish keeper and has been raising ornamental fish for decades. As a little boy, he drove his father crazy to buy him an aquarium with all the necessary equipment. Now, after a career in the field, he has set up Your Aquarium Place to offer the most comprehensive guide to ornamental fish keeping available and share his passion for the different species he has looked after.