Shigeyoshi Tanaka 

Marujyu Koi Farm (officially Marujyu Koi Farm) is a respected Japanese koi breeder located in Yamakoshi, Nagaoka, Niigata Prefecture. Currently run by third-generation breeder Tanaka Shigeyoshi, Marujyu is known for its refined approach to koi breeding and variety selection.

Specialization

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Marujyu specializes in Go Sanke, Tancho, and Goromo koi, along with various Ginrin (mirror-scale) varieties. After suffering heavy losses in the 2004 Niigata earthquake, the farm rebuilt with a focused strategy: breeding smaller numbers of high-quality koi, with particular attention to Tancho Kohaku, Kohaku, Showa, Sanke, and Goromo lines.

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Farm Overview

• Founded: Mid-20th century, now run by Shigeyoshi Tanaka (third generation)

• Location: Yamakoshi area, Nagaoka City, Niigata Prefecture, Japan

• Current Owner: Tanaka Shigeyoshi

• Facilities: Approximately 60,000 m² of breeding and raising area

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Reputation

Marujyu is respected for producing koi with striking clarity of color, elegant pattern placement, and refined body form. Its Tancho Kohaku and Go Sanke creations are particularly prized among collectors and hobbyists worldwide. The farm’s commitment to quality over quantity is reflected in the aesthetic consistency of its offerings.

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In Summary

Marujyu Koi Farm specializes in premium Tancho Kohaku, Go Sanke, and Goromo varieties, bred in small numbers but with exceptional quality. Rooted in the Yamakoshi region of Niigata, the farm’s legacy is defined by selective breeding, aesthetic excellence, and a renewed focus on elite Japanese koi traditions.