Note
All organisms that are typically grown by aquaculturists, from the largest fish to the bacteria in a nitrifying biofilter, require oxygen. In natural environments, oxygen sometimes limits production, though more often other factors determine the amount of biological activity and resulting biomass. In culture situations, however, oxygen is limiting because of the high stocking densities and feeding rates that are used. The culturist may, therefore, want to increase the dissolved oxygen (DO) concentration in the culture system by aerating the water.