Fish isn't what we'd call faked if it looks like a fish, it's probably a fish. But do you really know your snappers from your striped bass, or the difference between a farmed or a wild-caught salmon by its appearance? Many of us try to be picky about what species of seafood we buy, for environmental, health, or other reasons. But if you think you're buying grouper and you're actually given orange roughy (which is higher in mercury, and should be avoided by children and pregnant women), how can you hope to make educated choices?
Tip: Buy whole fish, instead of pre-cut filets, as it's harder for purveyors to pass off one species as another.