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Bettas – Siamese/Japanese Fighting Fish – Betta Splendens


Male Yellow Siamese Fighting Fish

Gouramis, of which family the Betta is most certainly a member, originate in Asia and have a form of lung which enables them to breathe air and make nests from bubbles.

Is the Betta a good community fish? The Betta should not really be considered to be a true community fish because it can be quite territorial and, at times, aggressive. Avoid including fin-nipping fishes like Tiger Barbs and other Bettas (especially Bettas of the same sex).

Key Facts

CategoryKey Facts
Common name(s)Bettas
Siamese Fighting Fish
Japenese Fighting Fish
Scientific nameBetta Splendens
FamilyOsphronemidae
Originate fromSoutheast Asia, specifically the Mekong basin of Cambodia, Laos, Thailand and Vietnam.
Care requiredModerate
TemperamentIn the wrong environment the Betta can be highly aggressive.
In the right environment the Betta can be a perfect community fish.
Colour & FormAvailable in a huge variety of colours and finnage styles
LifespanApproximately 3 to 5 years
Adult size2.25 inches to 3 inches
DietCarnivore or Betta food
Aquarium size10 gallon minimum recommended
Compatible withPeaceful and shoaling species
Avoid keeping withAggressive fish
Bigger Gouramis
Fin nippers (e.g. Tiger Barbs)
Never put 2 male Bettas together
BreedingEasy if you put the fish in the right environment.
Male builds a bubble-nest on the water surface.
Water temp75 – 80 Fahrenheit
Water pH6.0 to 8.0
Water hardness (dGH or dH)Less than 25 dGH

Origins of the Betta

The Betta (male shown above) originates from southeast Asia, specifically the Mekong basin of Cambodia, Laos, Thailand and Vietnam. As with many tropical fish, the Betta has also been introduced far and wide into different continents that have an appropriate climate.

There are over seventy species of Betta so it is important to clarify that this article will only deal with Betta Splendens, which is the specific species generally known as the “Betta” in North America. Should you wish to gain an overview of the full family of Bettas, then, in the first instance, you may wish to dive into its Wikipedia page

Characteristics of the Betta

As you can see, the Betta is an impressive fish which can grow to around 2.5 inches to 3 inches in size and live for around three years. The Betta is primarily carnivorous but selective breeding and commercial product manufacturing provides a wide range of foods that the Betta will thrive on.

Male Dragon Betta
Male Dragon Betta

There is a common perception that Bettas should be kept as solitary fishes or in a larger tank that is partitioned off so that they are, effectively, solitary. This perception is certainly valid in respect of keeping Bettas of the same sex in the same tank but I have successfully kept a male and female Betta in the same tank along with other peaceful community fishes. That said, I only keep them this way in tanks that are 36 inches in length (or more) that are also well-planted and properly filtered.

Bettas kept in a mixed aquarium (or in a single-fish aquarium) are both graceful and beautiful. Gouramis in general do, however, have a tendency to nip at the tails of fishes with elongated or elaborate finnage and Bettas are known to be aggressive fishes.

Mixed group of Bettas
Mixed group of Bettas

The male Betta is extremely territorial, especially when he is ready to mate and should never be kept in the company of another male Betta. The female Betta can also be somewhat territorial and aggressive, especially to other female Bettas. You can keep one male and one female Betta in the same tank of at least 20 gallons and well-planted is recommended. You should consider a tank of up to 40 gallons for a pair of mature, adult male and female Bettas to ensure that they have the room to thrive unless you are specifically in the process of breeding them at that time when they should be placed in a breeding tank undisturbed by other fishes.

Female Common Betta
Female Common Betta

As is true of all Gouramis, Bettas are extremely fascinating to watch. They tend to occupy the area of the tank from the top to the middle but will venture to all parts of the tank on occasion.

Much of the time, Bettas tend to move slowly and thoughtfully, it seems, not really using their pelvic fins as whiskers or feelers in the manner that other Gouramis do but they tend to swim forward then flare their fins (both the male and female) and, especially amongst male Bettas, this flaring is spectacular.

Half-Moon Nemo Betta
Half-Moon Nemo Betta

If a Betta is kept in a community aquarium and does not flare (or even hides away) then this is a sure sign that a more dominant fish is bullying the Betta so it would be appropriate to move the Betta into its own aquarium.

Bettas in tiny containers

There is a huge misconception that Bettas can be kept in dirty water. In their natural habitat, the Betta frequently lives in “blackwater” under the canopy of the rainforest, with very subdued lighting and little current. Being a Gourami, the Betta can live in water with low oxygen levels because it can (and does) take in air from the surface.

All water in nature has to circulate to be able to sustain life. The planet, essentially, has circulated its water constantly for millions of years and this circulation helps to cleanse the water and thus enables life to flourish.

If you keep your Betta in a bowl and don’t properly maintain the water then you are making your Betta live in its own toilet. Proper filtration and/or regular water changes are essential to the health and wellbeing of your Betta.

It is quite common for Bettas to be kept as a single fish in a tiny aquarium or even in a glass vase, oversized brandy glass or other “exotic” vessel. Pet stores sell complete “nano-tanks” are relatively low prices and many people believe that because this is fashionable that it must be okay.

Whilst this may be fashionable, it may not be wholly appropriate for the wellbeing of your Betta. It is a living creature and deserves to be treated respectfully, the same as any other living creature.

Bettas – Video

How do Bettas breed?

Bettas are labyrinth bubble-nesters which provides an excellent clue as to how they breed.

The most obvious ways to differentiate between the male and female Betta is that the male has a more striking colour and generally has a much more spectacular display of finnage.

Female Crowntail Betta
Female Crowntail Betta

The male Betta is generally the dominant fish and it will be the male Betta who ensures that the eggs hatch into fry.

The male Betta tends to become much darker when it is time to breed. The belly of the female Betta becomes larger as it is filled with eggs and she will develop vertical stripes along her flanks (the colouring of which will be determined by her innate colouring).

The breeding sequence is as follows:

  • The male will build a nest of bubbles on the surface of the water
  • If the female approves of the nest she will move under the nest
  • If she is disinclined to breed with the male then she will swim away (if the tank is sufficiently large) or may simply destroy the nest
  • The male and female will participate in the ritual breeding dance common to most species of Gourami
  • The male will embrace the female and squeeze her flanks with his body to encourage her to release her eggs
  • The eggs will fall to the bottom of the aquarium so the male will swim down, fertilize them with his milt then transfer every egg individually in his mouth into the nest that he has prepared
  • This courtship will be repeated until the female is spent of eggs.
  • The female will typically lay up to 40 eggs but could lay as many as 500.
  • Once the female is spent of eggs she should be removed from the breeding tank
  • The male will care for the nest and the eggs within until the eggs hatch (usually after around two days)
  • When the eggs hatch the fry will remain in the nest (with their tails hanging down) feeding off their yolk sac for around a further three days
  • The male will continue to maintain the nest
  • Once the fry become free-swimming (around five days after the mating) the male should also be removed.

Breeding tank for Gouramis

You should prepare a tank of around 20 gallons in size with mature, still water. Remember that in nature, Bettas thrive in still water. Ensure that there is plenty of floating vegetation in the tank (such as Indian almond leaves) but further ensure that there is clear water surface where the Bettas can take their gulps of air.

If the tank contains an air block and/or a filter then turn it/them off or the Bettas simply may not breed, as they require the water surface to be still.

The male Betta will start to build a nest of bubbles under the floating leaves into which he wants the female to lay her eggs.

Once he has built a substantial nest he will then entice the female to lay her eggs by performing a ritual dance which includes wrapping his body around hers and rolling her onto her side so that she deposits her eggs into his nest.

The male will collect any eggs that are not contained in the nest and place them into the nest. The female can lay up to 500 eggs but she frequently lays around 40 eggs.

Once the female has laid her eggs she should be removed carefully from the breeding tank because the male then becomes very protective of his nest and may well kill the female. He will certainly chase her away from his nest so she will have a miserable time until she is removed back to the community tank.

During the time it takes the eggs to hatch, the male will tend to the nest and protect the eggs until the fry are free-swimming out of the nest (usually around five days after the mating)

At this point, you can switch the filter back on and you should also remove the male.

Assuming that the breeding tank is a mature tank with a good collection of mature plants then the natural cycle of life in the tank will have produced the infusoria (a collective term for the microorganisms that help with the decomposition of plant material) that the fry (baby fishes) will consume once they are hatched. If in doubt, add infusoria at least daily for the first week after hatching.

You may wish to add some small, live brine shrimp or bloodworms, as the fry will probably have grown sufficiently to catch and consume them.

Should your Bettas have a special diet for breeding?

This is a much-discussed topic amongst aquarists. My personal belief is that all fishes should enjoy a rich and varied diet at all times including flake food, vegetable matter, live food and dried, live food. The fishes will themselves determine what they prefer to eat. In a community tank, fishes should be fed, as a general rule, once or twice each day and any food placed in the tank should be consumed within three minutes. The only exception to this is live food which the fishes will hunt down and devour.

Having decomposing food lying at the bottom of the tank is bad for the tank and bad for the fishes and, if you have catfish in the tank, they are not there as vacuum cleaners and should be treated with the same thoughtfulness as your other fishes.

If your fish are always maintained in the best possible condition then there is no reason whatsoever why any fishes should require a special diet to induce them to breed. You could make a point of feeding more than the usual amount of live food if you make any changes at all.

How varied can Bettas be in their colouring and finnage?

When I first started keeping Bettas back in 1972 (bear in mind that where I live is a relatively cold climate – and certainly too cold to keep Bettas without heating) you could generally only buy Bettas in Red or Blue (unless you had access to a specialist supplier) but selective breeding (for finnage, markings and colour) has resulted in there being a plethora of spectacular Bettas from which you can choose.

Common colours amongst Bettas include:

  • Alien
  • Candy
  • Cellophane
  • Copper
  • Galaxy Koi
  • Galaxy Nemo
  • Gold
  • Koi
  • Marble
  • Nemo
  • Opaque
  • Orange
  • Super Black
  • Super Blue
  • Super Red
  • Super White
  • Super Yellow

Less common colours amongst Bettas include:

  • Green
  • Grizzle
  • Lavender
  • Metallic
  • Mustard Gas
  • Super Orange
  • Turquoise

Colour patterns amongst Betters include:

  • Bi-colour – The fins must be a different colour to the body to be a Bi-colour.
  • Butterfly – The fins have distinct bands of colours
  • Cambodian – The body is pale, almost colourless, and the fins are a solid colour
  • Dragon – rich strong base colour with the scales on the main part of the body a pale iridescent
  • Full Mask – the face is the same colour as the body rather than what it would naturally be which would be darker than the body
  • Koi – Koi are judged from the top down and look like their carp counterparts. Patterns should be uniform with clean colour defining lines.
  • Marble – Irregular patterns throughout the body and fin
  • Multicolour – 3 or more colours on the body that does not fit into any other pattern category
  • Nemo – are either white-based or orange-based and have 3 or 4 main, additional colours including red, yellow, black
  • Pastel – A light shade of colour seen only on the fins, the body remains a flesh hue.
  • Piebald – pale flesh-coloured face irrespective of the body colour.
  • Solid – The entire fish is one colour with no variations

Finnage variations amongst Bettas include:

  • Comb tail – less extended version of the crown tail, derived from breeding crown and another finnage type
  • Crown tail – fin rays are extended well beyond the membrane and consequently the tail can take on the appearance of a crown; also called fringe tail
  • Delta tail – tail spread less than that of a half-moon [<180]
  • Elephant ear – pectoral fins are much larger than normal, often white, resembling the ears of an elephant
  • Feathertail – similar to the rose tail, with a rougher appearance
  • Half-moon – “D” shaped caudal fin that forms a 180° angle, the edges of the tail are crisp and straight
  • Half-moon plakat – short-finned half-moon; plakat and half-moon cross
  • Half-sun – combtail with caudal fin going 180°, like a half-moon
  • Plakat – short fins that resemble the fins seen in wild-type Bettas
  • Rose tail – variation with so much finnage that it overlaps and looks like a rose
  • Spade tail – caudal fin has a wide base that narrows to a small point
  • Veil tail – extended finnage length and non-symmetrical tail; caudal fin rays usually only split once; the most common tail type seen in pet stores.

Should you breed Bettas?

I guess that this question applies equally to all tropical fish but because Bettas are such a hugely popular fish, the subject merits particular attention.

We live in a world where almost everything has become a commodity. The Betta was pretty well unknown outside its native habitat until the end of the 19th century. I believe that the first Bettas outside of southeast Asia were introduced to Russia is the later days of Imperial Russia. Subsequently, they were introduced to France and then Germany in the last decade of the 19th century and then to the United Kingdom around the turn of the 20th century. I believe that it was around 1910 when Bettas were introduced to the USA.

Bearing in mind that, in captivity, Bettas are not usually kept together, consider that you have a pair of Bettas that breed and you then have, say, 40 fry to think about – some male, some female.

Where are you going to keep them? Are you going to buy another 40 tanks in which to home them or do you have a large cohort of friends eager to give your Bettas a home?

It’s unlikely that your local pet store will take them off your hands because your local pet store may be part of a conglomerate or may have a dedicated supplier and won’t wish to spoil that relationship.

Please don’t get me wrong, as I’m not suggesting that you do not breed your Bettas (or any other species of fishes, merely that you think it through carefully and understand what you are letting yourself in for.

Additional Resources

Mike Wheeler

I started keeping freshwater tropical fish in 1972 and it has been something of a passion ever since. In this website, my aim is to build up an everyman's guide to help the everyday aquarist get the best from this inspiring and entertaining hobby.

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