A method for farming fish (5) wherein the fish are kept in a desired volume of water. The method comprises the steps of selecting a volume of water delimited partially by natural barriers (2, 3, 4) to the fish (5) and providing an artificial barrier (6) for the fish (5) in the form of a virtual barrier of sound (10) adapted to provoke a response in the fish (5) and inhibiting them from passing the artificial barrier (6).