Trout have scales, and the Trout Farmers Association recommends breading trout for frying without removing the scales. For those who would still remove the scales, trout can be scaled very easily with a knife or even a garden hose.
Remove scales by running a knife or a jet of water from the nozzle on a hose against the grain, tail to nose. Alternately, simply fillet the fish and cook it. Some people claim that trout tastes better without the skin, while others enjoy the skin along with the rest of the fish, with or without the scales. Fry or bake trout at a relatively high temperature, but poach it without bringing the liquid to a boil.