Asagi and Shusui Koi: Origins, Appearance, and Key Differences

 

Asagi and Shusui are two beautiful and closely related koi varieties known for their calm blue tones and elegant patterns. These koi are popular among pond owners because of their unique look and historical importance in koi breeding.

 

Asagi vs Shusui: Key Differences

Although closely related, Asagi and Shusui differ mainly in scale type and pattern presentation.

• Asagi are fully scaled koi. Their scales form a beautiful net-like pattern across the back, usually in shades of blue.

• Shusui are considered a Doitsu (scaleless) version of Asagi. Instead of full scales, they typically have a neat row of large mirror scales running along the dorsal line.

• Both varieties often have red or orange markings along the sides, belly, and fins.

               ASAGI                             SHUSUI                             BUTTERFLY ASAGI

Origin and History of Asagi and Shusui Koi

The Asagi is one of the oldest recognized koi varieties in Japan. It dates back to the early days of koi breeding in the Niigata region of Japan, where farmers began selectively breeding carp for colour rather than food.

Early Asagi koi were bred from wild carp that naturally displayed blue-grey coloration. Over time, breeders enhanced the blue reticulation pattern and the red markings along the belly and fins.

Shusui was later developed in the early 1900s when Japanese breeders crossed an Asagi with a German mirror carp. The goal was to create a koi with the beautiful Asagi coloration but fewer scales. The result was the Shusui, literally meaning “autumn water” in Japanese, known for its clean body and distinctive row of scales along the back.

 

What Does an Asagi Koi Look Like?

Asagi koi are admired for their balanced and subtle beauty.

Typical features include:

• Blue or blue-grey back with a net-like reticulated scale pattern

• Red or orange (hi) coloration on the belly, cheeks, and fins

• Light or pale head, usually without heavy markings

• Symmetrical and calm overall appearance

The ideal Asagi displays a strong, even blue net pattern across the back with clean red accents that rise slightly up the sides without overwhelming the body.

 

What Does a Shusui Koi Look Like?

Shusui koi are visually striking because of their smooth skin and bold dorsal scale line.

Key features include:

• Scaleless blue body

• Single or double row of dark mirror scales running along the dorsal line

• Bright red or orange markings along the sides

• Clean, pale head with minimal markings

High-quality Shusui have a straight, evenly spaced row of dorsal scales and vibrant colour contrast between the blue body and red sides.

 

Fun Facts About Asagi and Shusui Koi

• Asagi is one of the foundation varieties of modern koi breeding.

• The word “Asagi” refers to a light blue colour in Japanese.

• Shusui was one of the first Doitsu (scaleless) koi varieties ever developed.

• The reticulated pattern on Asagi scales becomes more pronounced as the fish matures.

• Many koi varieties today trace part of their lineage back to the genetics of Asagi.

 

Feed Your Koi a High-Quality Diet

Like all koi, Asagi and Shusui benefit greatly from a high-quality diet. Good nutrition helps enhance their natural colours, supports healthy growth, and keeps them in great overall condition. Feeding a quality food all year round can make a big difference to their long-term health.

For everyday feeding, we recommend a Staple Diet as a balanced option. During the warmer summer months, switching to a Growth Diet can help your koi develop and reach their full potential

A well-balanced diet supports your koi’s overall health, helping them stay vibrant, strong, and healthy for years to come. To explore our full range of koi foods, [click here].

 

Enhance Your Pond with Asagi and Shusui Koi

Looking to enhance your pond with classic varieties? Discover our Asagi and Shusui koi today and enjoy the peaceful elegance they bring to your water garden.

Whether you’re drawn to the classic netted pattern of Asagi or the smooth, modern appearance of Shusui, both varieties add beauty and calm to any pond. Their soft blue tones pair perfectly with brighter koi and help create a balanced, eye-catching collection.

If you’re thinking about adding these timeless koi to your pond, explore our full range of koi [here].

 

For more information about koi variaties or advice on your pond, check out the rest of our blogs… 

The Ultimate Guide to Kohaku Koi: Origins, Traits, and Varieties |  Utsurimono Koi Varieties: Everything You Need to Know | A Beginner’s Guide to Sanke and Showa Koi: Origins, Patterns, and Key Differences