Asagi (浅葱 (Asagi))
One of the oldest varieties — blue net-like scales above the lateral line with red on the belly, cheeks and fins.
Asagi: Blue-grey reticulated (net) pattern on the back; red (hi) below the lateral line and on the fins.
| Pattern (JAS-aligned) | Blue-grey reticulated (net) pattern on the back; red (hi) below the lateral line and on the fins. |
|---|---|
| Colours | Indigo-blue above, red-orange below. The contrast sharpens with age. |
| How to tell it | Look for the net: neat rows of blue scales edged in lighter blue, with a clean white head and red rising from below. |
The variety in Japanese koi culture
Asagi reaches back to the earliest coloured carp of the Niigata mountains and remains the reference point for blue in koi. The word asagi describes a pale indigo, and the ideal fish shows that colour as an even net across the back, framed by red on the flanks. Because the pattern depends on scale-by-scale evenness, fine Asagi are admired for precision rather than drama. The scaleless or partly scaled Doitsu form of Asagi is known as Shusui and has its own page in this guide.
Keeping notes on this page are limited to generally published principles about the variety in Japan. This page gives no diagnosis, no treatment and no prescription for an individual pond or fish. For a fish that looks unwell, contact a veterinarian or your local fisheries office.
Sources: Wikipedia (CC BY-SA — summary in our own words, credit only); All Japan Nishikigoi Promotion Association official; Ministry of Agriculture, Forestry and Fisheries (MAFF) and Finance Ministry trade statistics as published; Japanese Agricultural Standard (JAS) for nishikigoi variety names and definitions (2022); Niigata Prefecture, Ojiya City, Nagaoka City (Yamakoshi) and Nishikigoi no Sato official; Japan National Tourism Organization (JNTO) visitor statistics; USDA APHIS and Australian DAFF official import guidance. Checked 6 November 2026.