Astrology.com explains that the Pisces symbol is a pair of fish swimming in opposite directions. The symbol has many meanings that relate to the personality of an individual born under the Pisces sign.
The two fish moving in the Pisces symbol symbolize a person with a fluid personality. The symbol represents easy-going individuals who don't like confrontation. The swimming fish represent calm waters.
Furthermore, given that there are two fish in the Pisces symbol, the symbol demonstrates the duality of a Pisces personality. Pisces personalities are said to be introspective and compassionate community members. There is a delicate balance between one side of the personality and the other side.