Sekiguchi Koi Farm

Sekiguchi Koi Farm is a Showa house, and their Showa are the reason to buy from Sekiguchi. Masayuki Sekiguchi, third generation at the farm in Minamitanaka, Minami-Uonuma, has the show record to prove it: a Sekiguchi-bred Showa took Young Champion at the 55th All Japan Nishikigoi Show in January 2025, the farm's fifth consecutive All Japan young-koi grand championship, and each of those five winners came from different parents. Before that run, a Sekiguchi Showa was Grand Champion of the 32nd All Japan Young Koi Show in 2015.

The farm started with Masayuki's grandfather Kosuke, who bred Kohaku, Sanke and Asagi. His father Kazuo worked in the dyeing trade until he saw a Tamagin, a koi with a pearl-like bump on every scale, and took up koi on the side. Tamagin lost the effect by age three. Kazuo fixed it so the scales kept their shine as the fish grew, and the result was recognised as a new variety, Pearl Ginrin. He then went full-time and built the Showa line the farm is known for. By 2005 output was roughly nine parts Showa to one part Pearl Ginrin, and the stated goal was bigger Showa, 80 to 85 cm, without losing pattern.

Two practical notes. Sekiguchi spawns in June, late even for Niigata, and Masayuki feeds the fry hard only until first selection and then stops pushing, because forced growth costs pattern. And Pearl Ginrin exists at this farm and nowhere else; if you want one it will be a Kohaku, Sanke, Tancho or Benigoi base. The farm is about 40,000 square metres, small by Niigata standards, so finished fish are limited.

ChampKoi imports koi from Sekiguchi Koi Farm. Look at their Showa first, and take a Pearl Ginrin when one turns up.