Abstract: A feeding system is for a closed pen for fish farming. The closed pen is provided with a water-supply system including a supply pipe which, at its upper portion, is provided with a housing with a lower portion, a middle portion and an upper portion, there being, extending from the middle portion of the housing, a feeding pipe which is arranged to convey water that is entering the housing at the lower portion to the inside of the closed pen. The feeding system includes a feed hopper and a feeder for carrying a feed out of the feed hopper and up to a mouth. The mouth is positioned at the upper portion of the housing. The housing is provided with a passage between the upper portion and the middle portion so that the feed is carried in the water and into the closed pen.