What is the symbolism of a Japanese koi fish and dragon together on a tattoo?

Answer 1

the koi fish turns into a dragon, according to Japanese folklore.

Koi Dragon TattooThe koi fish in Japanese folklore represents the overcoming of obstacles, because the koi fish travels up the yellow river and when it comes to the end of the river it transforms into the dragon; thus overcoming the adversity represented by the strong river to fufill its own destiny.

The Legend of the Rainbow River

Japanese legend has it that every year thousands of Koi, a courageous, strong, and dedicated fish, make a perilous and difficult journey up the Rainbow (or Dragon) river.

Out of perhaps a million Koi, only once in many years, one Koi is dedicated and strong enough to swim all the way to the head of the river, known as "The Dragon Gate" (or "The Rainbow Gate") and leap from the water.

He is transformed into a dragon. This tattoo tells the story of this little Koi's journey. Up the inside of the collector's calf swims the determined little fish. Against all odds he reaches the head of the River and leaps from the water. Above the metaphorical Dragon's Gate of the collector's knee, the koi-fish begins his transformation mid leap, becoming a Koi-dragon, before continuing down the outside of the collector's calf as a full fledged dragon.

Answer 2

There are many different possible meanings that could be behind a tattoo of a Koi fish and dragon. These could represent power and agility for example.