11 Betta Fish Facts (#9 will surprise you)

by Kevin

Betta splendens white and purple

Betta fish are one of the most popular tropical fish in the aquarium hobby.

But, betta fish may also be some of the most misunderstood aquarium fish; they are often kept in small tanks without filtration or heat.

My hope is that in writing this article about betta fish facts, you will develop a deeper appreciation for this feisty fighting fish.

Betta Fish Facts

Male dumbo betta fish.

1. A Filter and Heater Will Benefit Your Betta Fish

Aquarium filters help reduce waste and stabilize water chemistry by providing mechanical filtration (sucking up waste particles).

Some filters also provide chemical filtration, typically using activated charcoals and resins to remove waste matter.

Aquarium filters, especially sponge filters, also make ideal home for beneficial bacteria that that process harful substances like ammonia and nitrites.

Aquarium heaters are also a vital part of betta fish care because they help mimic a betta’s naturally warm environment, typically 78-84 degrees F.

Lack of a heater and filter are a big reason why betta fish do not survive long in captivity.

Low water temperature can lead to betta illness and a shorter lifespan.

The fact is, if almost any other aquarium fish were treated the way big box pet stores treat bettas (confined to small cups), those fish would die quicker than any betta.

Betta fish are resilient aquarium fish and when kept in a proper setup, can live well beyond the domestic average of 2-3 years.

2. Betta Fish Can Breath Air Just Like You

Male betta fish breathing air.

In fact, betta fish need to breath atmospheric air.

That is why you will see your betta constantly coming to the surface to grab a gulp of air.

If a betta has no access to air at the surface of a tank, they may actually suffocate.

Betta fish are able to breath air because they have a labyrinth organ, an adaptation that allows betta fish to live in smaller bodies of water, such as rice paddies and small ponds.

Fish that can breath air are known as anabantoids.

Betta fish, gouramis, and paradise fish (and their relatives) are all anabantoids because they have labyrinth organs and can breath air just like us.

Pet stores have taken advantage of a betta’s ability to breath air by putting bettas in cups and small containers.

While betta fish are able to live in these unhygienic, low oxygen cups for many days, they eventually perish when harmful bacterial and fungus are allowed to grow unchecked.

In the wild, betta fish and other anabantoids developed the ability to breath atmospheric air to survive dry seasons and low water conditions.

That does not mean they should be kept in tiny containers that mimic extreme conditions like droughts.

Bettas are actually found throughout Asia in environments where rain replenishes their habitat with oxygenated water.

In captivity, the best setup for a betta is a planted tank of 2.5-10 gallons.

3. Betta Fish Were Fighting Fish Before Being Pets

Two male betta fish flaring at each other in planted nano tanks.

In Siam (now Thailand), hence the name “Siamese fighting fish,” wild bettas were pitted against each other in gladiator matches.

People placed bets which betta would win, and the victor would often take home a sizable pot of money.

Breeders were quick to selectively breed for aggression and other traits like agility and stamina.

The popularity of these fighting fish intrigued European breeders, who began breeding betta fish for their color rather than aggression.

That’s why today’s betta fish, in all their magnificent colors and fin shapes, exist.

4. Betta Fish Need More Than Pellets

Commercial pellets are not terrible, but if you want to see your betta fish come alive, introduce him to live and frozen foods.

Bloodworms are probably the most well known live and frozen food for bettas, but there are numerous other kinds of worms and larvae that you can feed your fish.

Betta fish require more protein than many other fish, so make sure you are feeding your betta the right foods.

Frozen and live foods for betta fish include:

1) Mosquito larva

2) Tubifex worms

3) Glassworms

4) Mysis Shrimp

5) Cyclops

6) Bloodworms

7) Daphnia

5. Betta splendens is not the only type of betta fish

In fact, the genus Betta encompasses over 70 species of fish.

But, Betta splendens are what we commonly see in pet stores.

Betta splendens is also the most colorful type of betta because these bettas have been selectively bred for their color.

Others types of bettas are also striking, and serve as a reminder of the diversity of spectacular fish available to aquarists.

6. Betta Fish Build Bubble Nests Using Mucus

The male betta creates a bubble nest by blowing slime-coated bubbles at the surface of the water.

These bubbles may pop if exposed to cold air so providing a floating leaf or plastic lid for your betta to blow bubbles under helps ensure the survival of the bubble nest.

Male betta fish build bubbles nests to protect their young.

7. Male Betta Fish Care for the Babies

To the surprise of many, nature decided to make male betta fish the caretakers of baby bettas.

In the animal kingdom, males are typically more colorful while females are drabber and able to blend in with their environment.

The stealthier colors of females help her raise and tend to her young because predators simply cannot spot a female bird sitting on a nest, for example.

Betta fish go against this trend.

Male bettas prepare to raise fry by making a bubble nest.

After mating, a female betta will release eggs which fall to the bottom of the tank.

The male betta will retrieve these eggs and place them into his bubble nest.

Then he will chase the female away and guard the bubble nest.

Once the fry hatch, the male betta will continue caring for his young, and will dutifully suck them up with his mouth and spit them back into the bubble nest if they fry wander too far.

8. Betta Fish Can Live with Other Fish

Betta fish can live peacefully with a number of different aquarium fish, but keep in mind the following guidelines:

No fin nippers– your betta will not appreciate having his fins pulled on or ripped up by other fish. Sustained nipping may stress your betta and degrade his appearance.

No Betta-like fish – Male bettas attack other male bettas or colorful fish (like male guppies) that remind them of rivals.

Yes to plants and décor – Besides making the tank look fantastic, plants, driftwood, and large rocks give places to hide.

Yes, consider what each fish will eat – Betta fish require a diet high in protein. Keeping other fish that also thrive on high protein diets, rather than flake food, will make feeding easier.

Yes, consider tank size – Your betta will feel most comfortable with 5 gallons of personal water space to himself. If the tank is too crowded, fish may become stressed or aggressive toward one another.

Adding live plants to a tank can provide hiding places for fish and reduce aggression levels.

Live plants will also improve your water quality.

If you want to learn more about what you need to setup a planted tank for your betta, check out my article on easy planted tanks.

In general, peaceful community fish like Neon tetras, and bottom dwellers like Corydora catfish make great betta tank mates while nippy fish like tiger barbs and cool water fish like Goldfish make poor tank mates.

9. Betta Fish Can Learn Tricks

Betta fish performing trick by jumping out of water.

Now, don’t expect your fish to sit or stay, but some fish keepers have trained their betta fish to perform on command.

Similar to other animal training, consistently providing food or stimuli after a certain behavior will incentivize that animal to perform that behavior again.

Bettas are not different.

Check out this talented male betta fish:

10. Female Betta Fish are Aggressive

While not as aggressive as male betta fish, females will also flare their gills and display combative behavior toward other fish.

Many people wonder if female bettas can be kept together or if a male and female betta can be kept together.

Generally, keeping any two bettas together increases that likelihood that one of them ends up dead.

Some fish keepers establish betta sorority tanks of about 5 females.

But even in sorority tanks, female bettas will fight to establish a hierarchy, which may lead to an injured or dead betta fish.

Yes, I have seen betta sorority tanks work, but if you are a beginner or simply don’t want to monitor your fish constantly, keeping betta fish in separate tanks is a better idea.

11. Female Betta Fish Display Vertical Breeding Stripes

When a female betta fish displays breeding stripes, she is signaling that she is in good breeding condition and ready to mate with the male betta.

Only female betta fish display breeding stripes, which appear as lightly colored vertical bands.

Typically 5-6 vertical bands will be visible on the female betta’s body.

Female betta fish do not require the presence of a male betta to develop vertical bands, but if placed near a male, breeding bands may appear more rapidly.


Another fact is that betta fish make amazing pets.

They interact with you like few other aquarium fish do, swimming excitedly against the glass when they think you have food and flaring aggressively when they see their own reflection.

I hope you learned at least 1 new fact about betta fish from this article.

If you want to learn more about betta fish, check out my article on betta fish care.

And consider getting some live plants for your fish if he or she seems stressed or timid.

My review of some of the best low light betta plants should give you some ideas.

If you are a new betta fish owner and need a name for your feisty friend, check out my article on betta fish names.

As always, stay zen aquarists.