Koi Betta Fish: Overview & Care Guide (Pictures & Types)

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Last Updated: July 18, 2023 by Flora Gibbins

Today’s aquarium market offers a wide variety of pets you can care for, including Koi Betta for sale. You might have seen Koi-patterned Betta fish in a magazine or online and wondered if their care is different.

Do Koi Betta require different tank conditions? How do Koi Bettas compare to other variations of Siamese Fighting fish?

We have created this post to help you understand how these colorful little guys can provide you with a unique pet that stands out compared to other Bettas. Variety is the spice of life, and Koi Betta could be what your aquarium was missing.

What Is A Koi Betta Fish?

If you have seen this beautiful variety of Betta fish for sale online or in your local pet shop, you might wonder what they are. A Koi Betta fish is a descriptive title given to this variation of a Marble Betta fish – the name given to Betta fish that changes colors and patterns over time.

Koi Betta Fish Overview and Care

Color-changing occurs due to the “jumping gene” called Transposons. The name describes DNA sequences that can move along the genome. That mobility defines Marble Betta, and the term Koi Betta indicates a variation in color within that group.

We want to stress that a Koi Betta is not a hybrid Koi carp and Betta fish. The Koi Betta refers to the colors and patterns the fish display, which resembles a Koi fish.

So, where did this variation of Betta splendens originate? It was developed through breeding by keepers and not the deltas of South East Asia.

The fish has become more available on the fishkeeping market as it has gained popularity over the last several years.

What Is The Difference Between Koi And Marble Betta Types?


Before buying any Koi Betta fish for sale, you might ask what differences are between Koi Bettas and Marble Bettas. As we discussed previously, Betta Koi is a color and pattern variation of Marble Bettas. The two types of Siamese Fighting fish are similar in other aspects.

Many enthusiasts like to point out that Koi Betta colors are more distinct than Marble Betta fish. The Marble Betta tends to have colors that appear “fuzzy” along the edges, while Koi Betta’s colors form a sharper edge between colors. We want to stress that the “jumping gene” can affect these distinctions, so it is not a hard and fast rule.

Koi Betta develops their color and patterns over time, just like other Marble Betta fish. The Koi fish pattern has been developed over several years to resemble the multicolored variety of Amur carp – popular pond fish originating from Japan. It is worth noting that you see the colors and patterns more in Koi Plakat Betta than you will in others.

Galaxy Koi Betta Fish

Galaxy Koi Betta Fish

The Galaxy Koi Betta is a label placed on the Betta fish with specific colors and patterns. Male varieties display a base dominated by blues or reds. They will have less clear colors, though spots of iridescent scales are noticeable. The Galaxy Koi Betta has longer fins and tails than the Plakat.

Koi Plakat Betta Fish

Koi Plakat Betta Fish

Plakat is a variety of Betta bred with shorter fins and tails than other Betta fish varieties. The Koi Betta colors and patterns are more common in Plakat, which tends to have more Cellophane coloring than the previously mentioned Galaxy pattern.

Male And Female Koi Betta Fish

As you look to buy your Betta fish, you’ll need to determine if you want a Koi female Betta or a male Koi Betta. Like other variations of Betta splendens, the koi betta female fish appear different in several ways.

Koi Betta follows familiar color differences found with many Siamese Fighting fish. Males have more intense colors and patterns than females display. The females tend to display the patterns and colors on their fins.

How Large are Adult Koi Betta?

Koi Bettas have a similar size to other types of Betta fish. Males can be a bit longer than females, but a gravid female tends to have a wider girth. Koi Betta fish can reach about three inches in length, maximum.

Koi Betta Fish Temperment

Koi Betta has a similar temperament to other fighting fish varieties. They are aggressive by nature, and males will be more aggressive than females are.

You can create a community tank, but you will need to provide plenty of space to allow these fish to establish a territory. Tankmates should have passive dispositions and shorter fins that will not agitate the Betta Koi. Provide plenty of hiding areas to reduce the stress in the community aquarium.

Where Can I Buy Koi Betta Fish?

If these bright and colorful Bettas pique your interest, you will want to know where you can find Koi Betta fish for sale.

You may find them at big chain pet stores across North America, like Petco. It can be hit or miss when buying at large stores, as their stock of Koi Betta fish is not consistent. You may also observe that these tend to stock males since they are the more colorful gender.

Big-box stores like Walmart might have a pet section that carries Betta splendens, but the varieties available are random.

Your best bet for finding Koi Betta to buy is to look for independent stores specializing in aquarium keeping. You will find different types of bettas in various colors and tail types, including Koi Betta fish. They often carry females as well as males, and you might even find a breeding pair!

Another place to look is online. Betta clubs, specialized breeders, and online chain pet stores can supply you with Koi Betta. Most reputable online sellers will provide fast shipping and guarantee live arrivals.

Local breeders and shops will usually have websites, and you have the advantage of proximity. Even larger chains might advertise Koi Betta available at a local branch. National sources are your next best option as shipping is more reliable.

Online shopping overseas can be a gamble, and even reputable dealers may struggle to get Betta fish to you from halfway around the world. You will also pay more for shipment to get the fish to you promptly.

Trade magazines can also be a source for Koi Betta, but online sales have honestly taken over for selling at this point. Still, you may find local, national, or worldwide sources for Koi Betta fish.

Are Betta Koi Fish Right For You?

If you are a fan of Betta splendens in general, we can recommend the Koi Betta as a unique addition to your collection. As a variation of the Marble Betta, this fish expresses color development and changes over its lifetime.

Those new to fishkeeping will find the Koi Betta similar to keeping other types of fighting fish.

Finally, if you love the look of Koi carp but can not afford to house them, the Betta fish offers you the chance to enjoy the colors and patterns in a smaller fish, and you don’t need any outdoor space.

Do you have questions or comments? If so, leave them below so that we can continue the discussion. Enjoy your new Koi Betta!

Koi Betta Fish