Their unusual colouration and doitsu scalation have made Shusui firm favourites with koi-keepers. They tend to darken with age, however the colouration of a bright young Shusui can be quite startlingly beautiful.

Colours
The colour of the Shusui is basically the same as that of the Asagi. The head is blue-grey with hi on the jaws and the scales along the lateral and dorsal lines of the koi are darker blue than the rest of the koi. The skin on the back of the Shusui is an unusual pale sky blue.

Patterns
The pattern on the blue-grey head is the same as that of the Asagi. The body should be an even shade throughout the length of the koi, with two parallel stripes of hi.

Hana Shusui: This koi has hi markings between the abdomen and the lateral line and between the lateral and dorsal lines.
Hi Shusui: The hi of this Shusui spreads from the belly and covers the back.
Ki Shusui: This very rare Shusui is yellow with a greenish dorsal.
Pearl Shusui: This has silver scales and is rarely seen.

Scalation
This is an important aspect of the pattern. The scales along the dorsal line should be neatly aligned.