Tosakin
The Tosakin is a Japanese fancy goldfish variety from Kochi, developed for a broad undivided double tail that spreads and curls into a nearly circular fan when viewed from above. The body is short and rounded, and the tail carriage is the defining feature rather than speed or ruggedness. Tosakin are usually appreciated in shallow bowls or calm ponds where the top-view tail shape can be seen clearly. They are a specialized fancy goldfish, not a general pond fish.
Care is more delicate than for common goldfish or wakin. Tosakin need excellent water quality, gentle filtration, stable temperature, and protection from strong current that can damage or distort the tail. They compete poorly with fast fish, so feeding and tankmates should be chosen carefully. Breeders select young fish slowly, watching tail symmetry, body balance, and swimming ability. The same tail that makes the variety valuable can also make weak fish struggle, so welfare and movement should stay ahead of ornament.
Colors: Black, Black and Orange, Black and White, Blue-Gray, Brown, Calico, Chocolate, Gold, Lavender, Matte, Metallic, Nacreous, Orange, Panda, Red, Red and White, White, Yellow