In a large saucepan, combine the parsley, pimento, salt, pepper, tomato sauce, and fresh tomatoes. Bring to a boil. Add carrots, celery and garlic. Cook until carrots are cooked, but still firm. Stir in a little water and juice of 1 lemon. Place fish into pan without stirring. Baste fish with liquid. Add sugar. When the fish is cooked, remove from heat. Let cool and serve cold