The mix tank -a nutrient-replete, dark environment -operates as a completely stirred tank reactor and is well-mixed through intermittent sparged aeration. Mix tank effluent flows to the PBRs, where the microalgal community is exposed to light, a nutrient-deplete environment, and a single-pass time of 100 min. The median measured hydraulic retention times (HRTs) of the mix tank and PBRs are 3.3 and 4.3 hrs, respectively. Batch, bench-scale kinetic experiments were conducted for durations that exceeded the single pass times of the full-scale unit processes to better characterize the kinetics and stoichiometry of nutrient uptake and carbon storage and mobilization.