Remove scales, gills, and fins from fish. Wash with lime, vinegar, and water, then set aside.
Cut fish into steaks, or if you prefer, you can leave the fish whole. If cooking a whole fish, create small slices on each side of the fish.
Pat dry fish, then rub dry seasoning on fish. Be sure to get into the slices of the whole fish. Allow to marinate for 20 minutes or cook immediately.
Heal oil in a large skillet over medium heat. Add chopped onion and garlic, then saute for 1 minute.
Stir in the remaining vegetables. Allow vegetables to sweat for 2-3 minutes.
Add water and ketchup to the veggies and simmer for 5 minutes. Place fish over vegetables and cover for 5-7 minutes.
Add water to the container to remove any leftover seasoning. Pour into the pot. Flip the fish halfway through to cook evenly on both sides.
Adjust taste if needed and remove from heat.
Serve as desired.