Brush grill rack with vegetable oil. Heat grill to medium heat.
Place fish on grill rack. Cover and grill 10 to 20 minutes, turning once, until fish flakes easily with fork. Serve fish with salsa.
Leftover salsa also goes well over cooked rice or grilled chicken.
Limes at room temperature will produce more juice. Microwave each lime for about 15 seconds, or using pressure and the palm of your hand, roll it back and forth on the kitchen counter.