The growth rate, fatty acid profile and toxicity of 21 microalgae strains (Cyanophyceae (3), Chlorodendrophyceae (1), Xanthophyceae (1) and Bacillariophyceae (16)), isolated from coastal waters of Baja California (NW México), were determined. Cyanophytes Komvophoron sp. had the highest growth rates (p = 2.98 divisions day-1) and Aphanocapsa marina had the highest cell concentration (11.92x10(6) cell mL-1). xanthophyte Heterococcus sp. had the largest cell size (193.12 pm) with lower growth rates (µ = 0.67 divisions day-1). Fatty acid content differed according to taxonomic group. Diatoms contained the highest percentages of polyunsaturated fatty acids (n-3 and n-6 PUFAs), ranging from 23.4 to 60.7%, and eicosapentaenoic acid (EPA) was the most abundant. None of the residual media from the isolated microalgae strains were toxic to Artemia franciscana nauplii. We conclude that based on their growth rate, fatty acid profile, and lack of toxicity, all the isolated microalgae strains have the potential to be used alone or as part of a mixed diet for the culture of marine organisms.