Carrier for growing macroalgae, with an element provided for the growth of seeds deposited thereon, and having elements for suspension in a water volume. The carrier is a sheet provided with apertures allowing flow of water from one side to the other, the surface of the sheet having a structure which will retain spores and seeds. The invention is also directed to an arrangement for suspending such a carrier with a device connected to at least one part of an edge of the carrier. The device may be a platform submersed in the sea, to which the carrier is attached.
