Red shrimp, Farfantepenaeus brasiliensis, larvae's response to different concentrations of live foods (diatoms Chaetoceros gracilis: 20-100 x 103 cells/mL; flagellate Tetraselmis chuii: 2-10 x 103 cells/mL and Artemia nauplii [NA]: 1-5 NA/mL) was investigated in three experiments. Experimental assessments were based on four variables: survival rate, weight gain, development index (DI), and resistance to salinity stress. A combination of C. gracilis 80 x 103 cells/mL, T. chuii 2 x 103 cells/mL, and Artemia 4 NA/mL provided the best experimental response. Specifically, F. brasiliensis larvae fed with the above-mentioned optimal concentrations of microalgae and Artemia grew faster and reached the postlarval stage in less time (168 h) than larvae in other feeding regimes evaluated. The effect of C. gracilis concentration on larval growth, survival, and the DI demonstrated that microalgae-based foods could be a highly productive alternative to more traditional aquaculture feeding regimes.