I charge a French body of water to raise this seafood (8)
I believe the answer is:
calamari
'this seafood' is the definition.
(calamari is a kind of seafood)
'i charge a french body of water to raise' is the wordplay.
'charge' becomes 'ram' (I've seen this in other clues).
'french body of water' becomes 'lac' (I've seen this in another clue).
'to raise' says the letters should be written in reverse (in a down clue, letters go up).
'i'+'ram'+'a'+'lac'='iramalac'
'iramalac' reversed gives 'CALAMARI'.
(Other definitions for calamari that I've seen before include "seafood" , "Battered squid rings" , "Mediterranean cooked squid" , "Mollusc" , "Squid prepared as food" .)