Place the fish in a large nonmetal dish. Whisk together the 6 tablespoons oil, the orange zest, orange juice, ginger, hot sauce, salt, and pepper, to taste; pour over the fish. Cover and marinate in the refrigerator for 30 to 60 minutes.
Meanwhile, prepare grill. Brush the fish with additional oil. Grill until fish just flakes when tested with a fork, about 5 minutes per side for each inch of thickness.
Serve alongside Mango Coconut Rice.
In a large saucepan, heat the oil over medium-high heat. Add the rice and stir to coat with the oil. Add the coconut milk, water, and salt; bring to a boil. Stir in the mango. Cover, reduce heat to low, and simmer about 20 minutes or until the liquid is absorbed.
Remove the rice from the heat and fluff with a fork. Place a clean, dry dish towel over the pan, cover with the lid, and let steam for 5 minutes before serving.