The project calls for collaboration between workers within existing research programmes on larval rearing technology and larval nutrition of European marine finfish. Selected participants are involved in the diversity of larval rearing strategies, such as intensive rearing using Brachionus/Artemia diets and extensive/semi-intensive rearing using copepods. In addition, analytical facilities and expertise are available via the participating biochemists. The following objectives are outlined: 1. Review the use of live prey diets for marine fish larval rearing, particularly in relation to the culture of "new" finfish species such as halibut and cod, and compare to the culture of established species such as turbot. 2. By a combination of review and experimentation, evaluate the current copepod-based and Brachionus/Artemia based rearing techniques using turbot as a model species, covering all characteristic differences including behavioral, microbiological, environmental and nutritional aspects. 3. Review current knowledge on biochemical characteristics of the different primary and secondary diets, including any parameters relevant to nutritional value. Supplement with new analytical work to identify the important nutritional aspects of larval rearing. 4. Review the current status of halibut cultivation research, production and markets by reference to published data. 5. Evaluate future market prospects and production economics for halibut, and identify the research required to overcome technical and economic problems in the cultivation process.