The purpose of this paper is to present biomass and nutrient uptake data from Neochloris oleoabundans production in an open trough system. The growth medium used was BG11, temperature ranged from 16.7 A degrees C to 25.3 A degrees C, and pH ranged from 5.52 to 9.94 because the customary pH increase during algal biomass production was moderated by incoming CO2 gas streams (atmospheric, 2%, 4%, and 6% CO2). Peak concentrations of algal biomass ranged from 643 to 970 mg L-1, specific growth rates ranged from 0.15 to 0.37 day(-1), and doubling times ranged from 4.8 to 1.9 days. Carbon, nitrogen, and phosphorus were incorporated into the biomass at 0.05%, 8.3%, and 54% of supplied amounts. Open growth systems supplemented with CO2 should be designed to regulate medium pH within the range of 6.3 to 7.1. Future research should examine various media and alternative carbon sources to decrease doubling times, increase peak concentrations, and optimize nutrient uptake.