In an effort to evaluate the usage of natural diets in nursery feeding of Fenneropenaeus indicus (H. Milne Edwards) postlarvae, different feeding regimes that included commercial diet, natural diets and microalgae were tried out. After 10 days feeding, growth rate, survival, protein content, muscle RNA and RNA: DNA ratio of postlarvae fed mixed diet were significantly higher (P<0.05). Artificial diet alone fed postlarvae registered lowest values and were significantly poorer than rest of the treatments (P<0.05). No significant difference among treatments could be detected in trypsin activity (P=0.388). Correlation analysis confirmed significant relationship between growth rate and RNA: DNA ratio of postlarvae (r=0.90, P<0.001). Two weeks long pond experiment exhibited strong relationship between RNA: DNA ratio of postlarvae prior to stocking and post-stocking survival (r=0.78, P<0.001). Results from study confirm that supplementation of natural diets in artificial diet regime with or without inclusion of microalgae will enhance growth. But, presence of microalgae further improved the results by offering nutrition and stability. Pond experiments suggest possible use of RNA: DNA ratio as 'survival probability indicator' in commercial shrimp culture