The commercial production of Ulva spp. by aquaculture is gaining in importance due both to the qualitative and quantitative increase in the use of the harvested biomass and its new applications in inland IMTA techniques. However, very little is known about the specific culturing requirements and commercial quality of the different species of Ulva. The aim of this work is to try from this point of view four Ulva species that could be grown in southern Europe: U. australis, U. fasciata, U. ohnoi and U. rigida