ABSTRACTSuccessful rearing of marine fish larvae depends on numerous factors, but a suitable food supply in conjunction with reasonably good water quality are the two factors that are of greatest importance. Most newly hatched marine fishes have mouths that are too small to begin feeding on Artemia sp. nauplii, but some copepod nauplii, rotifers, mollusk larvae, and dinoflagellates provide suitable food. Size of food organisms and the food level maintained in rearing tanks are important for initiation of feeding and for subsequent growth and survival. Optimum rearing temperatures need to be determined for each species to assure that growth is rapid during the larval stage. Both growth and survival of fish larvae are enhanced when a phytoplankton bloom is maintained in the rearing system. Larvae grow and survive better in large culture tanks than in smaller ones.Little is known about optimum stocking densities of eggs and larvae in rearing systems. Abnormal development of larvae is a common occurrence and can be attributed to stresses of the rearing tank environment. Diseases and parasites may affect survival of eggs and larvae. Energy relations have been determined for egg and yolk sac larvae but similar research is required on advanced larval stages. The variability in egg quality that will result from artificial spawning procedures will also be a factor affecting subsequent rearing attempts.