A device and a method for the treatment of fish in a net cage installation are described where the device comprises a tank with a treatment agent the fish is treated in and where the tank comprises a conveyor mechanism for the fish in the tank. Also described is a system where a device to treat the fish is a part of a floating installation, such as a ship or a raft.A device and a method for the treatment of fish in a net cage installation are described where the device comprises a tank with a treatment agent the fish is treated in and where the tank comprises a conveyor mechanism for the fish in the tank. Also described is a system where a device to treat the fish is a part of a floating installation, such as a ship or a raft.
