Fry bacon in large pot until done but not crisp, Add the fish and fry in bacon drippings until lightly colored. Add paprika, mixing well, cover with water or broth. Bring slowly to a boil, reduce heat and simmer, partially covered. Add salt, pepper, marjoram, and the grated potatoes. Cook for 10 minutes.
Add the chopped tomatoes and cook another 10 minutes. While cooking, cover slices of pumpernickel with butter, cube them and toast them under the broiler until crisp.