Remove skin from filets; cut into 1-inch pieces. In large skillet fry bacon until done; add onion and cook until tender. Add tomatoes, potatoes, catsup and seasonings. Heat to boiling; reduce heat and cook, covered, for about 30 minutes, stirring occasionally. Add fish and continue cooking for another 25 to 30 minutes, until potatoes are tender. Stir gently on occasion. Serves 6.