The results of this trial indicate that FM content in low-FO diets formulated for longfin yellowtail can be substantially reduced using blends of SPC, H. pluvialis, S. limacinum and squid meals with no significant decrease in fish growth performance, feed utilization or intestinal integrity. Although the maximum inclusion of H. pluvialis as an ingredient may be limited by its reduced protein content, the incorporation of S. limacinum is not likely to be restricted by nutrient density, given its high lipid content and apparent value in aquafeeds for S. rivoliana and perhaps other species