bottom fish vs food fish

bottom fish and food fish both are nouns.

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

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

bottom fish: fish that live on the sea bottom (particularly the commercially important gadoid fish like cod and haddock, or flatfish like flounder)
food fish: any fish used for food by human beings

bottom fish (noun)	food fish (noun)
fish that live on the sea bottom (particularly the commercially important gadoid fish like cod and haddock, or flatfish like flounder)	any fish used for food by human beings