Crossword Genius

So a grass grows badly in this Atlantic sea (8)

Ross

I believe the answer is:

sargasso

(Other definitions for sargasso that I've seen before include "Gas soars around the North Atlantic sea" , "Seaweed giving name to a sea" , "Sea whence eels migrate" , "Sea with much floating weed" , "Sea, weedy part of the Atlantic" .)

I've seen this clue in The Irish Times.
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