Cut fillets into 1/2 - 1 inch cubes. Fry the bacon until it is crisp. Add the onions and brown them slightly. Add the water and the potatoes and cook for 10 minutes or until the potatoes are slightly tender.
Add the fish and cook until it flakes easily with a fork. Add the milk and seasonings and reheat. Serve immediately with chopped parsley sprinkled over the top.