Whether it be fresh yellowtail sashimi or a piled-high rainbow roll, Americans love sushi. But when faced with an encyclopedia of fish options, it’s hard to know what to choose.

There’s long been a rumor that when you order tuna at some sushi restaurants, you’re actually just getting a worse-quality fish dyed red with food coloring. So it’s no wonder diners often feel wary when perusing a sushi menu.

We spoke to sushi chefs across the United States about what they look for when they order nigiri, sashimi and rolls, plus the biggest red flags to avoid before you pick up your chopsticks.

Color Is Everything

All of our sushi experts agreed that the color of the fish is the No. 1 indicator that something’s not quite right. For chef Takeshi Ikeuchi, executive chef of Morimoto Asia in Disney Springs, Florida, it’s the first thing you should consider before taking a bite. “Diners should avoid anything that is dull or discolored,” he said.

Chef Masatomo “Masa” Hamaya, culinary director of O-Ku and Junto in Bentonville, Arkansas, confirmed this is the biggest dealbreaker. He explained, “When it comes to any kind of fish, when you see the color changing or any discoloration, it’s a red flag because it’s oxidizing, which isn’t a good sign.” Once a fish oxidizes, it begins to break down fatty acids and turn rancid.

It Shouldn’t Look Dry

Fish should have a natural sheen and luster, like it’s straight from the dock to your dish. Mitsuhiro Eguchi, corporate sushi chef at Nobu Chicago, said, “Dry fish means there is a loss of freshness.” The same goes for the rice. Eguchi said, “If the rice is too hard or dry, that means the balance is off. That’s a sign of poor rice quality.”

It Should Smell Like The Ocean, Not Like Fish

There’s nothing worse than a fishy smell emanating from atop your rice. However, sushi chefs note there is a major difference between an “ocean” smell and a “fishy” smell.

Hayama said, “Fish should exude the flavor of brine or the ocean. If you’re tasting the ocean, it’s full of umami because most fish have umami, and that’s normally a great sign. If it’s more fishy-fishy, then it’s about to be rotten.” And if the restaurant itself smells fishy, then it’s time to turn around and find a new sushi spot.

It Actually Shouldn’t Be Cold

You may think a cold piece of fish means it’s being properly refrigerated, but it’s a big sign the sushi chef isn’t a pro. Eguchi said, “Good sushi is served at a warm, human-touch temperature.” If there is a mismatch in temperature between the rice and the sushi, that’s how you know the chef’s sushi skills may not be up to par.

Always Judge The Display Case

Perusing the clear display case stocked with fish is part of the fun of going out for sushi. But chefs urge you to take a good long look at the products inside to decide the freshness and quality of what’s being served. “A well-organized display case and fresh-looking fish with a natural sheen are good signs,” Eguchi said. If the display case is left open for long periods or looks messy, it’s a sign the chef may not be taking hygiene and organization seriously.

Check Out The Actual Restaurant

The cleanliness of the actual restaurant was another unanimous must from the sushi chefs we spoke to. “Restaurant cleanness is definitely among the most important aspects when ordering sushi. It shows the chef values the condition of his restaurant and the quality of the dining experience for guests,” said chef Masa Shimakawa at Soko in Santa Monica, California.

Eguchi added, “When I’m checking out a sushi place, I pay attention to a couple of things. First, how clean is the counter? And what about the chef’s hygiene? If the chef is constantly wiping their hands, I feel much better about the food.” No one wants food poisoning or, worse, a trip to the hospital.

Top Ordering Tips

We’ve shared a lot of red flags and “don’ts,” but our experts have plenty of “do’s” for picking the best type of fish next time you’re out for sushi. Eguchi’s go-to is maguro (lean tuna) because it’s simple yet fundamental. He said, “Freshness and handling directly affect the taste.”

Tuna is also a favorite of Shimakawa. “I love to order different cuts of tuna, as this is a great indicator of the quality of a restaurant. A good sushi restaurant always has high-quality tuna available,” he insisted.

Ikeuchi recommends trying kohada, a small silver-finned fish. “It has a really rich flavor and is also a great way to see a chef’s skill level. It has a lengthy preparation process, including a marinating period in vinegar, and can be difficult to execute well,” he said.

When Hayama orders sushi, he switches between a classic tuna nigiri and mackerel or sardines because “sushi chefs always cure them,” he said. “In order for them to cure it correctly, some sort of technique is required. The way chefs cure is different from chef to chef, and I can tell by eating their mackerel or sardines just how great their culinary technique is.”