Abstract: The present invention relates to algal cell growth, modification and harvesting, and more particularly to systems apparatus and methods for growing, enhancing the growth of and harvesting of motile swimming microorganisms, especially unicellular algae, such as Dunaliella, which multiply by cell division.

Abstract: The present invention relates to systems, processes and apparatus for harvesting microorganisms, especially free swimming unicellular algae, such as algal cells of the Dunaliella variety.In accordance with one aspect of the invention, a material mass made up of fibrous or inert inorganic material in interposed between the liquid containing reservoir in which the algal cells are disposed for multiplication by cell division and the cell harvest zone to provide a preferred travel path for the migration of the cells from the reservoir to the harvest zone. This mass not only enhances cell travel from the reservoir to the harvest zone, but also acts as a cell collision mass to enhance cell division, thereby to decrease the time lag of cell division build-up in the early stages of generating an algal cell culture in the reservoir.