The seafood restaurant only has tuna, salmon, cod, or sea bass
"You know that a seafood restaurant knows what they're doing if they have fresh-shucked oysters. Anything that comes in live and has to be dealt with, processed, and served up in a short time frame means you're dealing with a higher-caliber restaurant. If you see steamed clams, mussels, or shellfish dishes, it tells me the restaurant's doing volume and they're treating their seafood great. If you see sea urchin, or other seafood you might not be totally familiar with that strays from the four major fish (tuna, salmon, cod, or sea bass) -- you know it's a good spot. Shrimp will also be frozen nine times out of 10."
The server can't tell you where the fish is from
"Talk to your server and ask them where the fish is from. The better places will be able to tell you. If the waitstaff doesn't know off-hand, it's not a black mark against them, but they should be able to get you the answer pretty quick, and tell you which state it landed in. If they say, 'It's from the Pacific' -- well, yeah, duh. I'm sure it is. If they can't tell you where it's from, they probably don't get in whole, fresh fish. It's probably portion-cut and frozen."
Oysters are not served properly
"If they're not serving oysters fresh-shucked on the half shell [Editor's Note: Ask your server if they do it!], and they won't do it for you that way, then it's probably not the best seafood restaurant to be in. If I went to a place that only had oysters Rockefeller, I'd put them in the same category as I would a chain restaurant. I'd be a little suspicious. It probably came in frozen -- you can buy oysters pasteurized and pre-shucked on the half shell. Instead, you'd want the restaurant serving oysters from a place closest to you geographically. I'd look for something that's as local as it can be."
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