The following proportions are for the production of a fine, well-flavored fish stock to be used as the basis of a fish velouté sauce. A smaller quantity of fish would produce a lighter stock suitable for fish-poaching, or fish soups.
Place all the ingredients in a 6- to 8-quart enameled or stainless steel saucepan or kettle. Bring to the simmer, skim, then simmer uncovered for 30 minutes. Strain through a fine sieve, and correct seasoning.
Fish stock may be refrigerated or frozen. If refrigerated, boil it up every 2 days to keep it from spoiling.