Betta fish are incredibly popular and, if you’ve ever ventured into the aquarium section of a pet store, chances are you’ve seen one.
You may even have noticed that each individual Betta was kept in its own chamber, separated from any others of its kind. Bettas are well-known for their fighting spirit, but that’s not the only interesting thing about them. Here are the most fascinating facts about Betta fish.
Bettas Are One of the Most Abused Fish in the Aquarium Industry
This fact is sad, but true.
Bettas can survive being kept in tiny, unheated and unfiltered cups, for a while. But, they will be completely miserable and much more prone to disease and early death.
Please, whatever you do, make sure that you keep your Betta in at least a 5 gallon (19 liter) aquarium that has a filter and a heater.
Tiny containers with no filters are terrible for Bettas. With no filter, the fish is forced to live surrounded by its own rotting poop that is constantly putting off toxic ammonia.
That’s pretty disgusting, so gross.
I’m fairly sure it’s considered a war crime if you do that to a human. So, don’t do it to your pet.
Also, Bettas originate from hot tropical waters. They need to be kept at temps of 75°F-82°F (24°C-28°C), much warmer than the average room temperature.
There are lots of options out there for Betta tank heaters, and they’re usually not that expensive.
And you don’t need a fancy or expensive filter. A simple sponge filter is what I recommend for Bettas, and they’re super cheap and easy.
For more information about aquarium filtration and the Aquarium Nitrogen Cycle, see our in-depth article here.
They Have Been Selectively Bred by Humans for Over 1,000 Years
A recent study into the genome of Bettas from the pet trade suggests that they have been in captivity for at least 1,000 years, making them one of the oldest domesticated species of fish.
There Are Over 70 Species of Betta
The vast majority of Bettas that you see in the aquarium trade are from a single species, Betta splendens.
But, scientists have identified over 70 species of wild Betta fish. Many look quite different from domesticated Bettas.
There are many kinds of wild type Bettas available in the aquarium trade, like Betta imbellis or Betta mahachaiensis, and they are beautiful!
Wild type Bettas have longer, more slender bodies than domesticated Bettas. Their fins are also much smaller, making them faster, more agile fish.
Tank raised Bettas can be quite lazy at times, but wild type Bettas are more energetic, faster swimmers.
Wild type Bettas are even more prone to jumping. They’ve been known to leap through tiny gaps between the tank lid and the filter. Keep them in a tightly lidded tank at all times.
All Species of Betta are Considered Gouramis
No matter what species of Betta, they are all classified under the suborder Anabantoidei, commonly known as gouramis. However, in the pet trade, Bettas are marked as Bettas and all other species of Anabantoidei are called gouramis.
These species of fish are all lumped together because they share an interesting feature, a crude lung that allows them to breathe gulps of air they grab at the water’s surface.
This lung, known as a labyrinth organ, is an adaptation that allows these fish to live in extremely low oxygen environments. They sometimes find themselves in stagnant, still waters that would be deadly to other fish species.
Low oxygen conditions are not ideal long term, but gouramis can at least survive until the next rainstorm washes in new water.
They Are Quite Aggressive
When Bettas were first domesticated, they were primarily bred to fight for human entertainment, like dog or cockfighting. Shamefully, this is still sometimes practiced to this day. Thankfully, it is largely illegal in the Western world.
This has left a genetic legacy for the fish we find in modern pet stores. Tank bred Bettas are quite territorial and aggressive.
Generally, males in the same tank will fight until one or both fish are dead. Females may also attack and kill each other, even after living together peacefully for quite some time.
Wild type Bettas are reported to be much more peaceful and docile, but I would still recommend keeping males by themselves.
Bettas Like it Hot
These fish originate from the Indochinese Peninsula in Southeast Asia. Native populations can be found in the Mekong River Basin in Thailand, Myanmar, Laos and Cambodia.
Winter temperatures stay in the high 80’s, on average, and summer temps average about 100°F (38°C).
It’s best to keep a Betta tank at 78°-82°F (26°-28°C). Lower temperatures can make them lethargic and less able to fight infections and other stressors. Low temps can also greatly hinder their digestion.
Male Bettas Raise the Babies
Male Bettas create bubble nests in their territories. They swallow gulps of air from the surface and then spit them back out under plant leaves.
These air bubbles have a fine coating of mucus from the fish’s mouth that acts like the outside of a balloon, holding the little pocket of air together. He’ll deposit hundreds of them to make a single nest.
When the male and female spawn, the male will carefully pick up the fertilized eggs in his mouth and place them among the bubbles.
After spawning, the male chases the female off and carefully guards the nest. He will scoop up any eggs or fry that fall out of the nest to put them back into place.
The male will continue to guard the nest until the fry are free swimming, usually about 6 days after the eggs are laid.
They Like to Take Naps
Bettas are a fairly low energy output kind of fish. They’re pretty much the opposite of fast-moving, hyper fish, like zebra danios or white cloud mountain minnows.
They do have bursts of activity throughout the day, but also quite a bit of downtime.
They will generally go to sleep while the lights are off, and you will even see them take little snoozes during the day.
Bettas will rest on plant leaves, along the substrate or inside decor and just chill out, sometimes for several hours at a stretch. Some even point their heads down into the substrate and let their tails float up towards the surface.
This can, understandably, scare new owners who think their fish has died.
If at all possible, try to not disturb a sleeping Betta, it scares them and stresses them out. Just give them a while, they’ll start swimming again after their nap.
For more information about Betta fish sleeping habits, see our in-depth article here.
Bettas Like Still Waters
Bettas originate from slow-moving waters, like ponds, ditches, vernal pools, rice paddies and slow moving tributaries of the Mekong River.
They are not strong or fast swimmers; it’s just not what they’re adapted for. And tank raised Bettas with big, showy fins are even less athletic than wild type Bettas.
Betta tanks should not have a strong water flow. This is why I recommend using a sponge filter for these tanks. An air driven sponge filter aerates the water well without creating a lot of water current.
Too much water flow in the aquarium can greatly stress a Betta. Having to constantly swim against the current takes up too much energy and will keep your Betta from being able to rest comfortably.
They’re Known for Jumping
In the wild, Bettas often inhabit vernal pools that can start to dry up as the seasons change.
If a Betta finds itself in an ever smaller pool, lacks food or can’t find a mate, they will jump out of the water and attempt to flop along the ground to find a better situation. Because Bettas can breathe air with their labyrinth organs, they can go much longer outside of the water than other fish.
Bettas will also leap out of the water to catch insects that fly by.
In the aquarium, Bettas have been known to jump out of their tanks, especially if the tank is too small or the water conditions are poor.
I highly recommend putting a tight-fitting lid on all Betta tanks. Keep your water parameters healthy with weekly water changes.
Bettas are Carnivores in the Wild
In their natural habitat, Bettas are tiny predators that feed primarily on insects and their larvae.
Bettas will also often eat small crustaceans, like daphnia and dwarf shrimp, and even fry from other fish. They actively patrol their territory, looking for any tiny creature small enough for them to eat.
Bettas are Omnivores in Captivity
Tank-raised Bettas are much more flexible than their wild cousins.
It’s good to feed Bettas a varied diet that includes both meaty foods, like shrimp, krill or whole fish meal, and plant-based foods that will provide fiber.
For more information on Betta food, please, see our in-depth article here.
Bettas are a very interesting kind of fish. With their beautiful colors and interesting behavior, it’s easy to see why they’re one of the most popular fish in the aquarium hobby.
I hope that articles like this one spread information that helps end the use of tiny containers that are not suited to house a Betta long term.
These gorgeous fish deserve a healthy environment so they can live long and happy lives.
I hope you find this article helpful.
I wish you and your fish the very best!