The invention relates to a system for transporting a flow of fish in water, comprising a number of pipes connected to each other by at least one valve. The valve comprises a housing 10, having one inlet 20 and at least four outlets 21, 22, 23, 24, the housing encloses a member 40 having a curved path 46 for accommodating the flow of fish in water. The member 40 is arranged to rotate around an axis A-A running axially through the centre of the inlet 20, and a first end 27 of the path is connected to the inlet 20 at all times. The valve also comprises an organ 44 for pivoting the member.The invention also relates to a valve to be used in such a system.