In fish farming, aeration is literally of vital importance. In addition to food, the fish need oxygen that is supplied in the form of tiny air bubbles (‘aerated’) to the water. But aeration has more advantages.
Also in the early days, lice were a major disease that salmon suffered from. Since salmon lice had an impact on harvest, the fish farmers had to look for solutions. For some reason - maybe it was an experiment or it happened by accident - they started to purge air from the bottom of the cage. And they observed that the movement of the fish started to change. Instead of circling day in and day out - as salmon normally do - they started to move around the cage and became more agile. If the salmon are more agile, the muscles have to work more, and meat from moving animals has a better quality. At the same time, the fish farmers detected that aeration helped them to create a more thermal friendly water environment, with an advantageous temperature, conditions and amount of oxygen. With result that the occurrence of salmon lice reduced. So aeration had - and still has - two advantages: improving the salmon quality, and reducing the unwanted lice. By the way: the words purging and aeration have the same meaning. ‘Aeration’ has the word air inside.