Fillet the fish or have the store do it for you. NOTE: 4 pounds whole fish should yield 2 pounds of fish fillets.

Rinse out the head of the fish and make sure that any bloody masses are removed.  Soak all of the bones and head in cold salted water to cover for 15 minutes or longer. Drain the bones and discard the water.

Place the bones and head on the bottom of a large dutch oven and cover with carrots, celery, and thinly sliced onion. Add the Bouquet garni and the 2-3 quarts of water to cover and simmer for 1 to 1 1/2 hours. Strain the liquid, reserve the carrots and set aside. Discard the bones, etc.

To make the fish, grind the fish twice in a grinder fitted with a fine blade or process in a food processor until a fairly smooth texture. Remove the fish to a large bowl.

Grind or process the onions, carrot and parsley and add to the fish.

Add the eggs, water, and matzo meal and salt and pepper and mix well with a fork until light and fluffy. NOTE: to check for seasoning, cook 1 teaspoon of the fish mixture in salted water for 10 minutes. Taste and then adjust seasonings if necessary. Never taste fresh water fish raw.

Shape the fish mixture in your hands to form ovals and gently place in a frying pan to which 1 inch of salted water has been added. Poach for 20-30 minutes (depending on size) over low heat or until center of 1 fish ball appears white. Drain on a cloth towel and cool in previously made fish broth. Serve with horseradish.