Preheat the grill to high heat.
While the grill heats begin seasoning the fish. Pour the olive oil over the red snapper. Then sprinkle half the salt, black pepper, garlic powder and paprika over the finish. Massage into the fish. Flip over and repeat. Flip the fish back over and sprinkle the dried parsley on top.
Cut the lemon in half. Juice one half of the lemon and drizzle over then slice the other half of the lemon and place on top of the fish.
Reduce the heat on the grill to low. Spray the grill grates with non-stick cooking spray. Carefully, place the fish on top of the grill grates. Grill with lid closed for 7 minutes. Using tongs, remove the lemon slices from the top of the fish and place on the grill grate. Carefully, using a spatula, flip the fish. Place the lemon slices back on the fish, close the lid and grill for an additional 7 minutes or until internal temperature reaches 165 degrees Fahrenheit and the fish is cooked through. Cut fish into slices (if whole filet), divide among plates, and enjoy immediately.