Preheat grill until very hot.
Drizzle the fish with the oil, and sprinkle with garlic and salt and pepper.
Grill the fish flesh side down for about 5 minutes.
Try not to let the fish stick by adjusting thefish with a spatula about every 2 minutes.
Flip the fish gently and grill another 5 minutes per side.
The fish should be firm to the touch and juicy.