The survival, development and growth of Litopenaeus vannamei protozoea (PZ) larvae were evaluated in three experiments during which they were fed five different rations of the diatom Chaetoceros muelleri , from emerging PZ I larvae until the day of change to mysis I. The total amount of food and energy supplied in 5 days to each larva ranged from 85.5 to 223.2 μg larva − 1 (ash-free dry weight) and between 2.25 and 5.88 J larva − 1 . After 2 days, the development index (DI) showed that some of the larvae fed the highest ration had reached the stage of PZ III.