Specific dynamic action (SDA) refers to the energy required to digest and assimilate food. This is measureable in terms of increased oxygen consumption and in some species of fish can represent a considerable fraction of the aerobic scope of the animal. This project aimed to expand the number of species that information was available for. Measurements of SDA were conducted by introducing a fish to a closed box respirometer and allowed to reach basal metabolic rate. The fish were then fed and both oxygen consumption and nitrogen excretion were monitored until they fell back to pre-fed levels.