What is a rare koi betta fish?

In this article we will discuss the rare koi betta fish.We will discuss everything about them from their habitat information, tank size,water parameters, feeding habitat, breeding behavior, diets and other parameters too.


In this blog

  • What is a rare koi betta fish?
  • Key specifications of rare koi betta fish
  • General characteristics of rare koi betta fish
  • Tank size of rare koi betta fish
  • Water parameters of rare koi betta fish
  • Tank mates of rare koi betta fish
  • Tank plants for rare koi betta fish
  • Substrate for rare koi betta fish
  • Feeding habits of rare koi betta fish
  • Behavior of rare koi betta fish 
  • Breeding of rare koi betta fish
  • Summary 
  • Frequently asked questions
  • Reference

What is a rare koi betta fish?

In their natural habitat,koi bettas are found in shallow, hot, stagnant pools, paddy fields and streams of Thailand.Often, these are just some of the only fish in these overheated hypoxic environments.

Koi originated through captive breeding by a betta breeder named Orville Gulley.He initially started raising them in peanut butter jars while in prison, as per some breeders.

Key specifications of Rare koi betta fish

Scientific nameCommon name Betta splendens rare koi betta fish
Other namesSiamese fighting fish
Habitat Freshwater of Southeast Asia
Diet Carnivore/omnivore in captivity
Temperament Aggressive like their cousins
Life span3-5 years
Conservation statusVulnerable (wild)Captivity (data deficient)

General characteristics of rare koi betta fish

  • Koi bettas is a strain of marble betta.
  • Koi bettas can be red, black or combination of both, but mostly they are a mixture of both the colors.
  • The koi betta is another variation of the betta with striking colors.They come in a variety of colors and are very popular among betta lovers.
  • Koi bettas are similar in size to other types of betta fish. Males may be a little longer than females, but pregnant women tend to have wider girths.
  • Koi betta fish can reach a maximum length of 3 inches,7.6 cm long. For this particular variant, having extra headroom for the fins isn’t very important.
  • Koi betta types-They have various other variants like fancy, galaxy,candy,tiger,nemo palkat and samurai koi bettas.
  • Koi nemo plakat betta is a very high quality fish with a variety of body and fins.
  • Galaxy koi betta is a label affixed to betta fish in a specific color or pattern.Male varieties show a base in which blue or red predominates. The spots on the iridescent scales are noticeable, but the color is not clear and they have longer fins and tails.
  • The average lifespan of a koi betta is 2-3 years.Optimal water conditions, low stress and abundant nutrients will extend longevity and quality of life.
  • Cape bettas change color naturally, but only very gradually compared to other bettas.In fact, it looks the same at four months old as it did at one year old.However, a sudden color change can be a sign of an underlying medical condition or a sudden change in water chemistry.

Tank size of rare koi betta fish

It is best to have a tank of at least 2.5 to 5 gallons to hold the koi bettas and kindly don’t put these carp bettas in a small bowl as this will stress them and shorten their lifespan considerably.

Betta carp should be housed in a tank of at least 5 gallons.They like swimming spaces and can easily get stressed in tanks that are too small for them.

Like other bettas, koi bettas too have a short lifespan and if they are kept in short and cramped tanks, they will die within one year.

Water parameters of rare koi betta fish

  • The water should be soft and have a neutral to weakly acidic pH 6.0-8.0. In addition, water movement should be minimized to mimic natural habitats.
  • Koi bettas work best at 75-84℉ and are tolerant of temperature fluctuations,but it should not be entertained as such fluctuations weaken their immune systems and make them vulnerable to opportunistic diseases such as ichthyophthiriasis or fin rot.
  •  Betta koi also prefer sources of tannins in the water.
  • Koi bettas like their cousins prefer soft water, but withstand a wide range of GH from 5 to 20 DH or 70 to 300 ppm. Very hard water can be harmful to them.
  • Carp bettas are more likely to die if they are kept in aquariums with high levels of ammonia, nitrite, or nitrate in water.It is very important to keep the levels of organic pollutants in check using an ammonia testing kit.
  • Koi betta needs a heater to keep the temperature constant and a vacuum cleaner to clean the tank.

Tank mates of rare koi betta fish

You can set up a community aquarium, but you will need to provide enough space for these fish to establish their territory.

Tankmates should have a passive disposition and shorter fins that will not disturb the bettas.Provide plenty of hiding places to reduce stress in the community tank.

Tank mates for rare koi bettas:

  • Female Bettas.
  • Corydoras, Plecostomus, and other bottom dwellers.
  • Larger shrimp.
  • Snails.
  • Gouramis,barbs,tetras,livebearers,danios, and other community fish.

Tank mates to avoid:

  • Fish with long colorful fins
  • Finnippers 
  • Aggressive barbs like tiger barbs
  • Cichlids

Tank plants for rare koi betta fish

Betta carp prefers densely planted aquariums with lots of hiding spots and rest areas. Living plants also serve as a source of food.

The ideal plants to keep with Koi are those that can thrive in very warm aquarium conditions.

Amazon sword plants(Echinodorus sp.)Hygrophila species, which are naturally found in the same region as bettas, and red root floaters (Phyllanthus fluitans) are some of the suitable tank mates for rare koi bettas.

Substrate for rare koi betta fish

Koi Bettas don’t care about the substrate.You can choose gravel or sand;whichever you think is best.Gravel is generally the most common aquarium substrate and is ideal for carp aquariums.

Spectrastone gravel is a mixture of small river pebbles aimed at giving the koi tank a natural look.

Feeding habits of rare koi betta fish

Koi do not have a specific diet.They are no different from traditional bettas.Some of the best foods to feed koi include red worms, brine shrimp and tubifex worms. 

Only feed brine shrimp and tubifex worms in small amounts as they are high in fat. Daphnia or water fleas are also fine,but they are also rarely fed because their hard shells have a laxative effect on Koi bettas.

When feeding pellets, aim to feed 2-4 pellets per feeding session. On the other hand, if you are feeding live, frozen, or freeze dried food, 2-3 is the optimal amount. It is also best to fast koi bettas once a week to aid digestion.

Behavior of rare koi betta fish

Koi bettas are just as aggressive as any other betta fish.They become very territorial towards other betta fish and will fight to the death. It is not uncommon for a male betta fish to show aggression even towards its reflection on the side of the tank.

Aggression is a common trait in all betta varieties.They have been bred in captivity for their aggression and that’s how they got this name fighting fish by betta breeders.

Koi bettas like their cousins prefer a schedule with regular light and dark periods so that they can enter normal sleep patterns and maintain a circadian rhythm.

Betta loves light, so he knows when to wake up and prefers a dark environment to sleeping.This gives your koi betta a regular sleep pattern that matches you.

Breeding of rare koi betta fish

Make sure to get a healthy  breeding pair and be sure to select fish from reputable breeders.You also need to choose male koi who don’t show any signs of illness.

The Koi breeding tank should be filled with water about 3-5 inches deep, which will allow the fry to easily reach the surface. Make sure there are enough covers in the tank, as koi like privacy when they mate.

The ideal water temperature is 76-84°F, and it is best to keep the pH between 6.0-7.0.Use sponge filters and water heaters to ensure optimal breeding conditions for your tank.

Introduce the koi betta pairs in the breeding tank and leave them to pair up for mating, once they are ok with each other, the male will start building bubble nests and will wait for the female koi betta to come over and lay eggs on them.

Once this is done male koi bettas like other bettas will protect their eggs like a doting father till they hatch and be sure to remove female koi bettas as they get very aggressive and can even kill or eat their eggs.


  • It is unlikely that you will see koi bettas in most pet stores. Specialty aquarium shops may sell them as exotics for betta enthusiasts, but you usually get koi bettas on special order.
  • Koi are usually slightly more expensive (between $12 and $20) than You may also find a koi fish that needs a new home. Sometimes they may be free, while others may charge a small fee for the entire setup.
  • Carp bettas may lose their color due to stress, old age, injury or illness. It can also lose its color naturally, especially if it has the marble gene. If they are black, you shouldn’t worry too much unless they show signs of other illnesses.
  • You can find koi bettas :Reputable online sellers,betta clubs and specialized breeders.

Frequently asked questions

Can you keep koi bettas together? 

Yes,koi bettas can be kept together and you should keep at least five females and one male koi fish.Do not keep two male koi betta together, as they are very aggressive and can kill each other to death.

Are Koi betta fish a plakats variety? 

Plakat is a betta with shorter fins and tail than other betta fish species. koi colors and patterns are more common in plakat,which tends to have more cellophane colors than the aforementioned galaxy pattern.

Are all marbled bettas considered as koi bettas?

Marbled bettas often have pigment spots all over their body and fins. The koi betta is a marbled betta, but not all marbled betta are koi.