A method for rearing fish of the Salmon salar species is disclosed wherein a pre-dietary feed comprising a fat content of less than 27% (wt/wt) is fed to the fish during a predietary phase throughout which the period of daytime increases for each subsequent day. After the end of said pre-dietary phase, a main-dietary Salmon salar feed having a fat content of more than 30% (wt/wt) is fed to the fish throughout a main-dietary phase during which the period of daytime decreases for each subsequent day. The feeding regime presented improves robustness and fish welfare, and reduces unspecific mortality.