We found the Marigot market a bit daunting, as many of the fish for sale, we could not recognize, and had no idea how to cook... There was a big beautiful mahi mahi being sliced up, but it had already been bought (in its entirety) by a dutchman, no others available. :>)
Another time we got very good fish to take home and cook from Skipjacks, 2 species, both were excellent.