Fish can move in all directions.Because the function of the muscles attached on either side of the spine. The contraction of the muscles of one side starting from the head to the tail. Reverb tail and back and forth of COD and tail.The head and tail to one to one. Pectoral fins and fin fin pairs hip, which is comparable to the front legs and the rear legs of livestock, respectively. Fin this pair is help the fish, and help to move up and down in the vertical.S switch to switch, where the fish are flat shape slender with mucus, making the fish moving in the water well. It reduces the friction of water while moving. But the shape and may make the body of the fish is more likely to tip over or roll easily.