A method for the production of biofuels from the open ocean comprises the steps: testing the currents to determine that a biomass remains in a zone suitable for harvesting; harvesting a portion of the biomass; and processing a portion of the harvested biomass to produce useful components of biofuels. An improved method of production of a biofuel comprises the additional steps of testing the ocean surface waters to determine any nutrients that are missing, and applying a fertilizer with any missing nutrients. The currents should be such that the biomass created stays in the ocean waters suitable for harvest rather than washed up on shores, or dispersed to other areas of the ocean. Suitable currents include ocean gyres such as the Sargasso Sea. Suitable biomass includes seaweeds that float in the open ocean and aggregate together in floating patches, such as the Sargassum weed in the Sargasso Sea.