Artemia nauplii are among the most commonly used cultured prey in aquaculture, but they may lack certain essential fatty acids pertinent to their target species. While enrichment can improve Artemia nutritional profile, enrichment procedures can cause undesired effects such as mortality and rapid growth, which is problematic for larvae with a small mouth gape. In this study we tested the effect of salinity (3–33), temperature (16–28 °C) and enrichment time (0–24 h) on survival, total length and fatty acid profile ofArtemia franciscana nauplii (marine strain) using a factorial design. Results were used to construct an A. franciscana nauplius enrichment model. Temperature was the most important forcing function influencing mortality, growth and fatty acid incorporation; temperature increase caused higher mortality, faster growth and more fatty acid incorporation. Salinity affected primarily growth and arachidonic acid (ARA) incorporation; lower salinities reduced growth and maintained higher ARA levels. The model allowed us to test different combinations of temperature and salinity, predict their outcomes, and consequently, choose the optimal combination of these abiotic factors and enrichment time to produce a prey with the desired properties (a specific total length and fatty acid profile), while minimizing mortality.