Our Artemia Cysts, also known as Brine Shrimp Eggs, have a hatching percentage of more than 90%. They will hatch into Artemia nauplii (baby brine shrimp) in 18 to 30 hours. Artemia nauplii are known to be the ideal live food for the first stages of many marine and freshwater tropical fish and for many invertebrates. Artemia nauplii are known to be the ideal live food for the first stages of many marine and freshwater tropical fish and for many invertebrates.