Cut fish into desired size pieces sprinkle with salt and set aside.
Add oil to pan. Add onion, ginger, garlic, and chili pepper. Saute 5 minutes. Deglaze with white wine. Let almost all evaporate. Add tomato, garam masala and curry powder. cook 2 minutes breaking up tomato.
Add in coconut milk, water and ketchup. Simmer 2 minutes. Add fish and cook another 4 minutes or until fish is done.