Breeder: Isa
Isa Koi Farm (伊佐養鯉場) is in Ojiya, Niigata. Hajime Isa founded it around 1970–71; his son Mitsunori Isa runs it today. The farm works 31 mud ponds, and Isa has always credited the mud itself for a good deal of the result.
Isa is a Showa farm first and foremost — Showa is reported to be around 70% of what they produce — with Kohaku and Taisho Sanke alongside. The Isa Showa is a named bloodline in its own right, built from a Dainichi Showa female and male lines from several other Niigata farms, and an Isa Showa took the Kokugyo prize at the All Japan Nishikigoi Show in 1997.
What Isa Showa are known for is being readable early. Sumi and hi tend to show at tosai and stay stable into adulthood, on big, bold, well-balanced bodies. That is not universal — Isa himself has said as much — but it is the farm's reputation, and it matters if you would rather see what you are buying than gamble on what a fish might become in four years.
Isa koi available now
Everything here was imported by House of Koi. We chose almost every older koi individually at the farm, and those are one-of-a-kind: each listing carries video of that exact fish with its size, sex and year born, and closes when that fish sells. Tosai are bought both ways: we pick many out of the pond ourselves, and others come as a mix we chose at the farm, in which case the listing covers a group of young koi rather than one named fish.
Our Isa selection is exactly what you would hope for from this farm: Showa, plus a Tancho Showa and a Tancho Kohaku short body.
Live koi ship Tuesdays and Wednesdays, anywhere in the USA. Browse all available Japanese koi.