In a small bowl, stir together the garlic powder, onion powder, paprika, lemon pepper, and sea salt. Sprinkle seasonings onto the fish.
In a small saucepan over medium heat, melt the butter with the garlic and parsley. Remove from heat when the butter has melted, and set aside.
Lightly oil grill grate. Grill fish for 7 minutes, then turn and drizzle with butter. Continue cooking for 7 minutes, or until easily flaked with a fork. Drizzle with olive oil before serving.