There has been a considerable amount of work on the effects of Artemia enrichment on shrimp larvae. However, the effects on the subsequent growth performance have not been thoroughly investigated. From mysis I to eight day-old postlarvae (PL8), shrimp (Farfantepenaeus paulensis) were fed either newly hatched Artemia nauplii or Artemia enriched with an emulsion containing high levels of n-3 highly unsaturated fatty acids (n-3 HUFA). Upon reaching PL8, shrimp were exposed to salinity and total ammonia (TAN) stress tests. Growth performance was assessed by further rearing shrimp for 40 days. Shrimp fed the enriched Artemia (named EG) had higher tolerance to both salinity and ammonia than those fed newly hatched Artemia (named CG). Weight of PL from EG was also higher than in CG. Higher levels of n-3 HUFA, especially 20:5n-3 and 22:6n-3, were found in the enriched Artemia. In the postlarvae, higher levels of n-6 and n-3 HUFA were observed in EG, while PL from CG presented higher levels of 18:3n-3 and 18:4n-3. At the end of the nursery rearing, no differences in survival were observed, but weight was higher in EG (1.08 g) than in CG (0.90 g). The supplementation of n-3 HUFA during larviculture increases the tolerance of F. paulensis postlarvae to salinity and ammonia, and positively affects growth performance after a 40 day long rearing period.