Nutrient and population dynamics accompanying algae-bacteria interaction were observed in unialgal, 18-liter batch cultures during a light-dark cycle. The green algaChlorella vulgaris, and the nitrogen fixing blue-greenAnabaena flos-aquaewere inoculated with an aquatic community of bacteria. The bacteria community enhanced the regeneration of nutrients. Of special note, is the observed generation of soluble nitrogen in the synthetic growth media via nitrogen fixation followed by mineralization.