This experiment examined the growth response of Chlorella vulgaris exposed to CO 2 concentrations increasing from ambient to 8.5% and under white, blue, red and red-blue lights after 15 days incubation. Biomass production increased with increasing CO 2 concentrations under all light sources. The highest biomass production, 1.59 g L -1 , was obtained when the algae were supplied with 8.5% CO 2 and exposed to white light. Biomass production under blue, red and red+blue light was 1.53 g L -1 , 0.45 g L -1 and 1.27 g L -1 , respectively. The research suggests that C. vulgaris is not able to adapt production of its photosynthetic pigments to absorb light sources different that it is normally has evolved to.