Marine fish larvae are among the smallest vertebrates on Earth and are particularly challenging to culture in captivity . One of the key challenges in rearing these animals through the early life stages is providing adequate nutrition to support larval growth, health and survival. Marine fish larvae often require cultured live feeds, such as rotifers and Artemia , for their primary food source. However, cultured live feeds are an inferior food source when compared to the natural prey of marine fish larvae, copepods, and require enrichment to improve their nutritional value. Water-soluble nutrients are particularly challenging to manipulate in culture live feeds since the very small size of the enrichment particles are inherently prone to nutrient leaching when suspended in water . Liposomes are a type of microparticle that encapsulate water-soluble nutrients by means of a phospholipid bilayer (lamella) and are commonly used in human medicine for the delivery of pharmaceuticals and other bioactive compounds . We have found that liposomes can be adapted for use in aquaculture and are highly efficient for the delivery of water-soluble substances to aquatic organisms. We have used liposomes to control the concentrations of vitamin C and taurine in rotifers and Artemia. We then performed larval feeding trials with increasing concentrations of taurine and/or vitamin C and measured the resultant changes in larval growth and survival. The response of marine fish larvae to these manipulations has varied by species and will be reported in this presentation. In addition, we have conducted trials to evaluate the effects of the carrier particle on the growth and survival of two species of marine fish larvae. Our results suggest that liposomes produced with saturated soy phospholipids can be used for the enrichment of live feeds without negatively impacting the growth or survival of California halibut (Paralichthys californicus) or white seabass (Atractoscion nobilis) larvae.