The Ryukin can grow to 8 inches (21 centimeters) in length with some reports as long as 10 inches in larger aquariums and ponds.
The Ryukin is thought to have originated in China but its’ name is Japanese it was said to have arrived in through the Japanese Ryukyu Islands. Ryukin historical references date as far back as 1833, but it is thought to have first landed in the Ryukyu Islands as early as the 1770s.