Butterfly Koi Fish

What Makes this Beautiful Fish so Unique?

Have you ever heard of fish snobbery? Well, it exists. Perhaps the most prevalent form of freshwater fish snobbery exists in the koi breeding cycles and involves the angelic-looking butterfly koi. 

Two varieties of Koi Fish
Two Ornamental Butterfly Koi Fish

A Glance at History

Butterfly koi are a relatively new breed on the pond fish scene and can trace their lineage back to the late 70s when fish connoisseur Crown Prince Akihito of Japan suggested that an Indonesian carp be bred to a Japanese pond smelt.

A few years later, breeding resulted in the beautiful rendition that fish enthusiasts covet. Koi are technically carp, though they no longer resemble wild carp. But the lineage produced beautiful ornamental fish.

Onagagoi translates into long-tailed carp; it was the son of a breeder who coined the name butterfly. Acceptance by the traditional koi community takes time. While the original butterfly koi offspring still swim in the Imperial Palace koi pond, snobbery prevails.

Butterfly koi are often banned from traditional koi fish shows and competitions. But it hasn't diminished their popularity in America. 

Not surprisingly, as a long finned koi, Butterfly koi are also known as longfin koi.  Additional nicknames based on their long flowing fins include dragon carp and dragon koi. They are a pleasure to watch in an outdoor pond. Learning about Koi has allowed me to get acquainted with their mesmerizing beauty and their quirky personalities.

Let Me Clarify Some Key Points for You

What makes butterfly koi so unique? And are they a suitable investment in time and money for my family?

  • Let’s look at variations in color and patterns
  • Where to buy
  • What to expect when creating a backyard pond oasis
  • Life expectancy
  • Creating a fish-friendly environment
A photo of a variety of Butterfly Koi
A Variety of Colorful Butterfly Koi Fish

A Fish Friendly Habitat

Taking on a pet always comes with a responsibility, and fish need constant care too. While koi are versatile, you must meet specific requirements whether you opt to keep them indoors for the year-round pleasure of watching them swim or outdoors in a pond. A fishbowl is not an option.

Tank or Pond Options:

  • Young koi can remain in a 29 indoor gallon tank.
  • Rule of thumb: tank and pond size must be at least 50 gallons per fish.
  • Be three to five feet deep.
  • Not in direct sunlight.
  • A calm area of the house or yard.
  • Butterfly koi have fragile fins; therefore, transferring with fish nets is essential
  • Quarantine newcomers before introducing them to others.
  • Invest in quality filtration/aeration system and proper food.

Why? Because they are living beings and deserve our commitment and protection.

Pond Considerations:

  • Koi can tolerate broad temperature changes 
  • In winter climates, ensure they have breathing space and install a de-icing system that prevents water from becoming a solid block of ice.
  • Koi will hibernate, and it's common for them to stop feeding when temps drop below 40F - having a pond thermometer is a must for anyone with a backyard koi pond - especially in colder climates

How? Create a backyard oasis for you and your butterfly koi. And watch as the fish eat from the palm of your hand.

Two different Butterfly Koi Fish
Various Butterfly Koi color morphs and Variations may be found all around the world.


While providing you with countless hours of pleasure, the butterfly koi fish has several admirable qualities that make them a unique species. However, butterfly koi size does limit who should keep them.

  • On average, they live 25-30 years but can live for 50 years and longer in ideal habitats.
  • They may reach 40 inches in length.
  • Weight 30+ pounds.
  • Able to learn feeding from your hand.
  • Beautiful finnage.
  • They do just fine in an outdoor pond with standard koi and will eat the same pond fish food

What about colors and patterns? Ah! I’m leaving the best for last.

What to Expect

Butterfly koi are distinguishable by their elongated finnage and have personalities too. As with any relationship, the more time you invest, the more you’ll receive in return.

  • Maintaining a safe environment becomes your responsibility when you purchase Japanese koi fish, it takes effort.
  • There is a cost to providing high-quality pellet food that can complement an occasional treat of shrimp, earthworms, soldier flies, etc.
  • Please don’t overfeed; it’s not to their benefit.
  • Consider hiring a professional for pond construction - they'll make sure your pond is at an adequate depth and that any decorative water features that are added provide proper aeration and water flow.

Three Butterfly Koi Fishes
A Shoal of Butterfly Koi Fish

Best Place to Shop for Butterfly Koi

What has this world come to? You can buy anything on the internet, and they’ll ship it in a box. But make no mistake, this trip in a baggie and container is stressful for any animal. 

I’m still a firm believer in that out-of-date customer service practice, which should also be a prevalent trait from online koi fish merchants.

Look For:

  • A reputable seller will provide a guarantee.
  • Their website is professional.
  • Offer tested fish with KHV and SVC certifications.
  • Quarantine their product.
  • Know their business.
  • 5”-6” butterfly koi range from $50-90.

But where? Most often, our interest is anchored in our experience. So if you met a butterfly koi in a pond, ask the pond owner. Information is always your best guide.

A variety of Butterfly Koi with different colors
Brighty Colored Butterfly Koi Fish with Various Patterns

Hallelujah! The Pretty Ones!

What is striking about butterfly koi is their feathery translucent fins and their gorgeous color and pattern variations. You already know about fish grading if you’re a hardcore butterfly koi enthusiast, which sets the prices. 

Butterfly koi fish are an investment, and what draws people’s attention is their elegance and the endless varieties available to consumers. Key breeds are Kohaku, Sanke, Showa, Ogon, Bekko, Shusui, Asagi, Doitsu (scaleless), and Ginrin.

  • Sanke butterfly koi are perhaps the most traditional koi version, recognizable by the novice. Orange, black, and white, they stand out in a pond or tank.
  • Doitsu Platinum Ogon and Tancha Kujaku are the silver ghosts skimming through the water like a precious ornament.
  • Ginrin Yamabuki Ogon is perhaps my favorite in gold and white as it glitters like a bauble.
  • Beni Kikokuryu in silver is simply striking.

Frank Salvatore

In 2015 our family moved into a house south of Denver, Colorado with a  koi pond.  Since that time I've learned to really enjoy the koi fish and the pond. This blog is dedicated to providing helpful hints and information for koi pond hobbyists - as well as those of you who just inherited a koi pond and are thinking NOW WHAT?

About Me

Hey there - I'm Frank Salvatore. In 2015 our family moved into a house south of Denver, Colorado that had a Koi pond. The problem was I knew absolutely NOTHING about koi ponds.

This blog is dedicated to providing helpful hints and information for koi pond hobbyists - as well as those of you who just inherited a koi pond and are thinking NOW WHAT?
Learn More About Me

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