Season both sides of the fish with salt and pepper. Put the flour in a shallow bowl, dredge the fish, tapping off the excess flour to create a light coating.
In a medium nonstick fry pan, heat the 3 tablespoons olive oil over medium heat. Cook the fish until golden brown, about 3 minutes per side. Transfer fish to a plate.
Wipe out the pan with a paper towel and heat the remaining 3 tablespoons olive oil over medium heat. Add the garlic, tomatoes, water, parsley, 1/4 teaspoon salt, and 1/2 teaspoon pepper and cook at a simmer for 10 minutes. Add the basil and the fish and heat for 2 minutes. Serve immediately.