6 Koi Fish Facts You Need to Know

Koi fish are colorful ornamental fish known for their long lifespan, large size, and cultural significance, making them one of the most popular pond fish in the world.

The ancestral form of the fish is the Amur carp (Cyprinus rubrofuscus), but the domestic strains are very distant in appearance from the wild carp.

These fish are usually kept in outdoor ponds or garden water bodies. They have a rich history in Asian culture dating back thousands of years.

1. Koi Fish means “brocade carp” in Japanese

Koi fish means “brocade carp” in Japanese and refers to its colorful and patterned appearance.

Koi is actually the informal name for this species. They are often called Japanese koi or by their Japanese name, nishikigoi.

In Japanese culture, koi symbolize luck, prosperity and good fortune. Many people even have koi fish tattoos to represent these qualities.

A koi fish was first exhibited in Tokyo in 1914, propelling its popularity throughout Japan and leading to selective breeding in Niigata.

2. Pet Koi Fish Are Kept in Ponds

Koi fish live in outdoor ponds when kept as pets, although their wild relatives are found throughout Asia.

Koi ponds often include rocks, waterfalls and aquatic plants.

Special measures may be necessary in winter, such as using an aerator to prevent freezing. You can also move your fish to an indoor pond, although this is rarely necessary.

When selecting fish for your pond, remember that smaller fish will grow larger over time. A typical koi measures between 14 and 18 inches and requires approximately 250 gallons per fish.

3. The lifespan of Koi fish is very long

Koi fish typically live 25 to 50 years, although some live up to 100 years.

With proper care, koi fish can live for decades. Water quality, nutrition and preventive health care all play a role in lifespan.

4. Koi Fish Prices Can Vary Widely

Koi fish prices vary widely depending on size, color, lineage and pattern.

Small koi typically cost between $8 and $50, while some can exceed $100.

The most expensive koi ever sold was $1.8 million in Japan.

Factors that affect price include:

• Genetic lineage: Highly sought after bloodlines are more expensive.
• Variety of Koi: The most popular varieties are Kohaku, Sanke and Showa.
• Model: Steps (colored bands on the dorsal surface of the fish) and symmetry of patterns can often increase the price of a koi.
• Size: Larger fish 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 accommodate all the koi you intend to purchase if they are not fully grown yet.

5. There are many types of Koi fish

There are over 100 types of koi fish, grouped based on color, pattern and scale type.

Koi are divided into 16 groups by Zen Nippon Airinkai (the original koi club), a club that oversees koi breeding and judging standards.

Three main colors make up many varieties of koi:

• Red (Hi)
• White (Shiro)
• Black (Sumi)

Other commonly seen colors include:

Some koi have a metallic sheen called “gin rin.”

It is common for koi to be tri-colored, but they can also be single, two-colored, or multi-colored.

6. Koi fish can get very big

Koi fish can grow up to 3 feet long depending on the variety and environment.

Adult koi require around 250 gallons per fish, while large or breeding koi may need up to 500 gallons.

Overall, koi fish make great pets for those who can give them the time and space they need.