Here’s how and why some fish change color. PetMojo. 10 Pet Fish That Change Color. Story by Monika Dimitrovska ... Koi Fish. Koi fish, like most fish on this list, have vibrant colors, ...

The value of a Kōhaku koi fish decreases if its sashi — the soft edging of a koi’s color pattern — is thin or looks greyish. Some less valuable subspecies are Komoyō, Makibara, Kuchibeni ...

The nation’s top koi aficionados will bring their most spectacular fish — up to 3 feet long — to South San Jose to compete this weekend, April 5-6, in the ZNA NorCal National Koi Show.

Besides its long lineage, the unique color pattern of Taisho Sanshoku koi contributes to its high value. The most expensive one, a Maruten Sanke, fetched $341,990 at a Sakai Fish Farm auction in 2015.