Based on a literature review the article shows alternatives to the commercial feeding of carnivorous fish. There are only a few studies about how, respectively in which extent fish can be fed with a diet with low amounts of fishprotein and fishoil, without any negative effects on health or quality. Those food components described are mainly of plant origin. The aim of this study was to find new components useful as feed additives for commercial fish feeding. In these studies it was possible to find both, some promising components (for example barley protein) as well as some which could be excluded. Potato protein concentrate was found as not appropriate because of the food acceptance, although the amino acid amount and profile is of high quality.