Any salmon, sockeye included, can go from moist to overcooked in a minute's time. The easiest way to prevent an overcooked, dry piece of fish is to use a digital meat thermometer to track the internal temperature of your fillets as you cook. Once the thickest part of the fillet is a few degrees below your target temperature, remove the fish from the pan, oven, or grill and cover it with foil. This will allow residual heat to raise the temperature another couple of degrees. This carry-over cooking will allow you to enjoy moist sockeye salmon that is cooked to your liking. For well-done fish, aim for a final temperature of 145° F. For medium-rare or medium salmon, aim for 125° F to 130° F.