With this simple trick, you'll be able to grill fish to perfection very time you BBQ.
Heat, Clean, and Season Your Grill
Treat your grill like a cast-iron pan—you want it smoking hot, clean, and well seasoned. Heat the grill on high, then scrub the grates with a grill brush to remove ash, debris, and bits of food. Dip a square of folded paper towels in oil, hold it with long-handled tongs, and wipe grates until they're glossy—this forms a coating between the grates and fish to prevent sticking.
Prepare and Cook the Fish
Thick, skin-on fillets and steaks (think salmon, halibut, snapper, and grouper) hold up best. Pat the fish dry and brush both sides with oil. Place skin side down perpendicular to grates. Cook, covered, over direct, medium-high heat until skin is brown and crisp. If the fish doesn't budge when you try to flip it, keep cooking until it releases. Flip with a sturdy spatula and grill until cooked through.