salmon vs food fish

salmon and food fish both are nouns.

Word	Noun	Adjective	Verb	Adverb
salmon	Yes	Yes	No	No
food fish	Yes	No	No	No

As nouns, food fish is a hypernym of salmon; that is, food fish is a word with a broader meaning than salmon:

salmon: any of various large food and game fishes of northern waters; usually migrate from salt to fresh water to spawn
food fish: any fish used for food by human beings

Other hypernyms of salmon include salmonid.

salmon (noun)	food fish (noun)
any of various large food and game fishes of northern waters; usually migrate from salt to fresh water to spawn	any fish used for food by human beings
a pale pinkish orange color
flesh of any of various marine or freshwater fish of the family Salmonidae

salmon (adjective)	food fish (adjective)
of orange tinged with pink