Koi fish tattoos typically represent luck or fortune; they can also represent Yin and yang represent balance and the belief that all things are connected. Koi fish tattoos often incorporate various symbols, such as the yin - yang symbol, water and fire, dragons, or lotus flowers. Here is what each of. Two koi fish placed in a circular shape represent yin yang, a Chinese philosophy that. Koi tattoos placed with lotus flowers symbolize purity and.