Koi Varieties Guide: How to Choose Your Japanese Koi
Every koi at House of Koi is a one-of-a-kind fish imported directly from breeders in Japan — the koi in each listing's video is the exact fish you receive. This guide explains the major varieties in plain English so you can choose with confidence.
The Big Three (Gosanke)
Kohaku is the classic red-and-white koi and the foundation of the hobby — crisp white skin with a bold red pattern. Sanke adds black accents along the back for a balanced three-color look. Showa is built on black skin with wrapping sumi beneath red and white — bolder and constantly developing as it matures.
Black-Based Koi (Utsurimono)
Utsuri koi pair deep black skin with a single contrast color: white (Shiro Utsuri), red (Hi Utsuri) or the rarer yellow (Ki Utsuri). Strong Utsuri are judged on the crispness of the boundary and the depth of the black.
Blue Koi
Asagi is one of the oldest varieties — a blue-grey net-like scale pattern with warm red along the sides. Shusui is its scaleless (doitsu) counterpart: sky-blue skin, one line of dark dorsal scales, red flanks.
The Friendly Koi
Chagoi, Soragoi and Ochiba Shigure are famous for growing fast and taming quickly — usually the first fish in a pond to eat from your hand, and the fish that teaches the others to trust you. If you're starting a pond, one of these is the best first koi you can buy.
Metallic Koi
Ogon are single-color metallic koi — Platinum (white), Yamabuki (gold) and more — with a mirror-bright sheen. Kujaku and Kikusui combine metallic skin with pattern for maximum flash.
Special Traits
Ginrin koi carry sparkling, diamond-like scales. Doitsu koi are scaleless with a glossy, clean finish. Tancho koi carry a single round red crest on the head — a mark that cannot be bred on demand, which makes good Tancho genuinely scarce. Butterfly koi have long, flowing fins. Pattern-shifting varieties like Kumonryu and Matsukawabake redraw their black patterns over time — the same koi keeps becoming a new one.
Common Questions
What is a tosai?
A tosai is a one-year-old koi, usually 4–10 inches. Tosai are the affordable way into quality Japanese bloodlines — you grow the fish out yourself and watch the pattern develop season by season.
How big do koi get?
Most well-kept Japanese koi reach 20–28 inches at maturity; jumbo bloodlines can exceed 30 inches. Growth depends on pond size, water quality, temperature and feeding.
Are your koi really from Japan?
Yes — our koi are sourced directly from Japanese breeders such as Omosako, Kanno, Dainichi, Ogata, Shinoda and others. Each listing names the breeder, and many browse pages are organized by breeder.
How do I know which exact fish I'm getting?
Every individual koi listing includes a video of that exact fish, plus its measured size, sex, year born and breeder. What you see is the fish that ships.
Which koi is best for beginners?
Chagoi, Soragoi and Ochiba Shigure — hardy, fast-growing and famously friendly. Pair one with the varieties you find most beautiful; the friendly fish will teach the rest to hand-feed.
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