I got this from another site, just modified it to my liking.
2 tablespoons good olive oil
1 cup chopped yellow onion
1 tablespoon chopped garlic
1 28 oz. can plum tomatoes, drained and diced
1 teaspoon kosher salt
1/2 teaspoon fresh ground black pepper
1/2 cup dry white wine
1 2-3 pound striped bass fillet skin removed
1 lb large shrimp shelled and deveined.
pre heat oven to 350 degrees f
heat the oil in a large saute pan and saute the onions over medium heat for 10 min. or until the onion is translucent.add the garlic and cook for 1 more min. Add the tomatoes,salt,pepper and white wine and simmer for 5 min. lay the fish in a 10 by 14 baking dish and sprinkle with salt and pepper. add the shrimp. pour the sauce over the sea food and bake uncovered for 30-35 min.
try it you will enjoy, I also did this adding mushrooms. I don't know how much the filets wieght but they covered the whole dish.