Mix all ingredients in a blender, make into a dough. Add just enough flour to achieve a sticky but soft texture. Refrigerate for 2 hours. Boil a pot of water. Shape fish dough into small balls. Carefully put in the boiling water. Cook for about 5 minutes. Using a colander spoon, ladle out the fish balls and put on a serving plate. Serve with your favorite sauce (ketchup or tomato sauce are good). Garnish with some celery leaves (optional). You can also add seasoning to the water and make it into fish ball soup. (In case the fish balls break apart, this is a good choice.)