Koi fish are an extremely popular and colorful form of the fish species Amur carp (Cyprinus rubrofuscus). These fish are commonly kept as an ornamental fish in outdoor ponds or garden water features. They have a rich history in Asian culture dating back thousands of years—but are not related to goldfish despite their similar coloration. Their bright vibrant colors and behaviors can provide a splash of color and activity to any outdoor pond.
Koi Fish Meaning
Koi is actually the informal name for this species—they are often referred to as Japanese koi or their Japanese name, Nishikigoi. Nishikigoi is known as the “swimming jewel.” In Japanese culture, koi fish are often kept since they symbolize luck, prosperity, and good fortune.
A koi fish was first displayed in Tokyo in 1914—propelling their popularity around Japan. This was also around the time selective breeding started in Niigata, Japan, which developed and spread worldwide.
Koi Fish Pond
Koi are commonly kept as pets in outdoor ponds. Ponds can be great ways to enjoy your Koi and even provide a scenic landscape to your property, since they often include elaborate rockwork and waterfalls. Koi are temperate freshwater fish that can adapt to water temperatures between 45-95 F. When keeping koi, it is recommended to keep them at a temperature between 68-75 F. A deep pond can maintain a thermocline (temperature gradient) in the water, allowing koi to experience different temperatures.
A deep pond will also make it easier for koi to stay in the pond during winter. Water can freeze anywhere between 18-24 inches deep in a pond. Ensuring your pond is deep enough will prevent your fish from freezing. During the winter, koi will go into torpor or dormancy when the water temperature reaches 45-50 F. Their bodies will shut down and will not require as much food. A pond heater can be added to increase the temperature of the water to ensure koi survive winter temperatures. Special measures can be taken if your pond freezes over during the winter. For example, creating a hole in the ice and adding an aerator can help your koi survive.
When selecting fish for your pond, remember that smaller fish will grow over time. Knowing how big your fish will become as an adult is important to determine how many fish can be kept in a pond. Generally, every inch of fish requires about 10 gallons of water. So a 100 gallon pond can have a 10 inch fish.
Prices of Koi Fish
Koi can range in price due to many factors. Typically, a small koi will run anywhere between $8 to $50. Some koi, depending on size and color, can cost over $100. The most expensive koi ever sold at auction was for 1.8 million dollars in Japan at the 2017 All Japan Koi Show.
Factors that determine the price point for koi may include:
Genetic lineage: Highly sought after lineages are more expensive
Koi variety: The most popular varieties include Kohaku, Sanke, and Showa
Pattern: Steps and symmetry in patterns often can increase the price of a koi
Size: Larger animals are more expensive
Origin: Imported animals are more expensive than domestically produced animals
Number of fish purchased: If koi are purchased in bulk the price tends to be lower. Make sure you can house all the koi you intend to purchase if they are not fully grown yet
Koi Fish Color
There are over 100 different varieties of koi that are separated into 16 groups based on Zen Nippon Airinkai (the original koi club) who oversee the breeding and judging standards of koi. Koi can be differentiated by coloration, pattern, and scalation. New varieties of koi are constantly being developed by selective breeding.
Three core colors make up many koi varieties: red (Hi), white (Shiro), and black (Sumi). Other colors that are commonly seen include yellow, orange, blue, and cream. Some fish may have a silver or gold metallic sheen to their appearance. It is common for koi to be tricolored but they can also be either single, bicolored, or multicolored.
How Long Do Koi Fish Live?
Koi, when provided with the correct environmental conditions, can live between 25-50 years on average. Reports of koi living to 100-200 years do exist—the oldest koi ever documented lived to be 226 years old. Water quality, pond conditions, nutrition, and preventative health care can help improve the longevity of a koi’s lifespan. There are many commercial koi fish foods that are available to pet parents, and can be used exclusively to feed koi and provide complete nutrition. Overfeeding is a common concern that can lead to health issues.
Providing appropriate vet care can help improve the lifespan of any koi. Not all veterinarians will treat fish, so be sure find a veterinarian who specializes in your pet. Organizations such as the American Association of Fish Veterinarians (AAFV) and Find a Fish Vet function can help assist in finding a vet that has experience treating koi.
Featured Image: iStock.com/Appfind
WRITTEN BY
Sean Perry, DVM
Veterinarian
Dr. Sean Perry completed his undergraduate degree at the University of California, Santa Cruz, earning a Bachelor of Science in...
FAQs
A black koi is said to bring good luck. Koi are very smart and will recognize the person who feeds them. You can train koi to eat out of your hand if you're patient. Koi are prone to sunburn so it's important to shade the surface of the pond with plants like waterlilies, water lettuce, and water hyacinth.
What are some fun facts about koi fish? ›
A black koi is said to bring good luck. Koi are very smart and will recognize the person who feeds them. You can train koi to eat out of your hand if you're patient. Koi are prone to sunburn so it's important to shade the surface of the pond with plants like waterlilies, water lettuce, and water hyacinth.
What is unique about koi? ›
While koi are often associated with their vibrant colors, they are also fascinating when it comes to their dietary habits. Koi are omnivorous and possess a diverse palate. They consume a wide range of food, including algae, plants, insects, and even small crustaceans.
What are koi known for? ›
Koi Fish Meaning
Koi is actually the informal name for this species—they are often referred to as Japanese koi or their Japanese name, Nishikigoi. Nishikigoi is known as the “swimming jewel.” In Japanese culture, koi fish are often kept since they symbolize luck, prosperity, and good fortune.
Can koi fish live for 100 years? ›
Koi are beautiful and long-lived fish, living up to and past 100 years in optimal conditions. In domestic ponds, they typically live around 15 to 30 years. Japanese koi often live 40 years or longer. The oldest koi fish on record was around 200 years old!
How many days do koi live? ›
On average, a koi fish's lifespan ranges from 25 to 30 years. The key to a long life for your koi fish is to provide them with a healthy environment. This means a pond with clean water, lots of plants, and plenty of room to swim. Koi are also very resilient fish.
How old is 2 inch koi? ›
You can usually tell the age of a koi by its size. For example, a 2-inch koi is likely in its first year of life, while a koi of 4.5 inches or longer is one year or older.
What does 12 koi fish mean? ›
12 koi fish meaning have strong symbolic meaning Japanese, Chinese Feng Shui Meanings include: Tenacity, Courage, Wealth & Abundance.
How fast do koi grow? ›
Due togenetic predispositions, most Koi will reach a size of 20 inches if cared for properly and in the right environment. Under the right conditions, the average Koi will be between 6 and 8 inches by the end of its first year, and by the time it is 3 years old it will have reached its full adult size.
Do koi fish have teeth? ›
While koi do have teeth, they are not razor sharp or pointed or jagged. Koi teeth are smooth and rounded, like molars. And since their teeth are in the back of their mouth, you would have to reach down their throat to feel them!
Koi are actually very intelligent – they have trained you to feed them on demand! All joking aside, Koi fish are known for their great memory, loyalty to their owners, and for their striking personalities.
What does koi eat? ›
What Do Koi Fish Eat Naturally. In the wild, koi fish eat algae, plants, insects, worms, seeds, and anything they can stir up from the pond's bottom. They hunt along the pond floor and along the surface. If you have an ecosystem pond, they can continue having their natural diet.
Why is it called koi? ›
Modern Japanese koi are believed to date back to early 19th-century Japan where wild, colorful carp were caught, kept and bred by rice farmers. The word “koi” comes from the Japanese word for “carp.”
Does koi fish bite? ›
So could a koi bite you? Not unless you plan on sticking your hand way down its throat. You might be able to catch a glimpse of them if you look hard enough, especially in younger fish, but their teeth are way too far back to put your fingers in jeopardy. Koi also pose little danger to their pond mates.
How big can koi get? ›
Most domestic Koi usually grow about 12 to 15 inches long. Japanese Koi usually grow 22 to 26 inches in long. Jumbo sized Koi grow up to 34 to 36 inches long.
Are koi fish almost extinct? ›
The Eurasian Carp, the species that Koi originated from, is considered vulnerable to extinction within its native range. In other parts of the world, it is considered a non-native invasive species.
How fast can koi fish swim? ›
A healthy 50 cm koi will probably be able to cruise continuously at 2-5 km per hour. Compare that with a tuna Thunnus albacares with a burst speed measured at 20.4 m/s (73 km/h) or a black marlin Istiompax indica measured at 36.1 m/s, a staggering 129 km/h.
Do koi like to be touched? ›
Not only can koi fish get to know you but they can also follow you as you come close with food and make interactions creating a special bond. Petting and hand feeding koi fish allows you to engage with these vibrant and graceful swimmers in a whole new way, while also enjoying a calming and therapeutic experience.
Do koi fish like being touched? ›
It depends on the fish. Some fish do enjoy being petted. However, it's very important that you wash your hands meticulously and use soaps that don't leave any residues at all. (A scrub with plain salt might help — rinse well).
