In conclusion, our results demonstrate that there is considerable room for marine ingredient sparing in diets for giant grouper, and that SBM, SPC, and ALG show promise in this context, replacing at least 40% of marine ingredients in this study. The level of soy protein concentrate and algal meal inclusion in the diet could be increased above 50% of the total diet weight if supplementation with essential amino acids is done, although this requires corroboration by additional studies. As for a cost-effective use of Schizochytrium as the main lipid source, its commercial production costs need to be below those of fish oil and other lipid sources used in formulated fish diets.