In this work the effect of the hydrodynamic conditions to different aeration rate (1.4, 1.8, and 2.4 vvm) and two internally lit, annular FBR geometries (airlift and bubble column) on cell growth, nitrogen removal and lipid production of Chlorella vulgaris were evaluted. A two-step nitrogen reduction cultivation mode was used for promoting lipid accumulation. The inoculum was cultivated at an initial concentration of 90 mg L-1 N-NH4+ (nitrogen sufficiency) and at the end of the exponential phase it was fed to 11 L FBR at a sufficient dilution to start with 20 mgL-1 of N-NH4+ (nitrogen reduction). The results showed that at similar aeration rates, very different hydrodynamic regimes were attained in each FBR, being more turbulent in the airlift geometry. However, the degree of stirring and mixing did not cause cell damage or photoinhibition. Celular growth of up to 12 × 106 cells mL-1 were observed, nitrogen consumption was always between 16 and 19%, and calculated shear rates were in the range of 120-340 s-1. The major lipid productivity was reached at 1.8 vvm (0.650 and 0.528) mg·L-1 d-1 in annular bubble column and airlift geometries, respectively.