What Do Fish Use to Swim?

Fish use their fins to swim and their swim bladder to regulate buoyancy. Generally, fish have five fins: pectoral fins, pelvic fins, dorsal fin, anal fin, and caudal fin. Some fish also have adipose fins. Among these, the caudal fin provides the propulsion for swimming and also helps control the direction when turning. When fish need to slow down, the pectoral fins come into play, while the other fins primarily help maintain balance.