Prawn rearing is increasing due to increase in human population and increase in human consumption and its ability to generate income. However, the use of Artemia nauplii as live food is expensive and small farmer cannot afford it. Problem with the partial replacement with egg custard are short shelf life. Plus increase workload of the farmer to prepare the egg custard as it can long last within two weeks only. Natural feed additive such as herbs and spices can act as natural preservative as well as can contribute benefits towards the growth performance to the prawn. Storage conditions play a crucial role in extending the shelf life of egg custard. Low temperature storage condition can retard the growth of bacteria and turn the food into ice as it is freezing. Different composition 1%, 3% and 5% of C. longaand M. oleifera used in this experiment resulted in different bacteria colony count in the egg custard stored under three different condition which is freeze (-4 °C), chiller (20 °C) and room temperature (27 °C). Samples were spread on the nutrient agar place for three time throughout the two weeks. The optimum bacteria colony count was observed in treatment control, 1%, 3% and 5% were chose for proximate analysis to determine the changes between before and after the treatment. The optimum bacteria colony count for treatment control and 1% is stored under chiller condition were 1.16x106 cfu/mL and 1.51x106 cfu/mL respectively while for treatment 3% and 5% is stored under freezer condition were 2.47x106 cfu/mL and 3.35x106 cfu/mL respectively. In conclusion, treatment 5% stored under freezing temperature shows the best nutrition composition that meet the prawn larvae feed requirement after 14 days of treatment.