Making a show-stopping fish dinner means getting high-quality fresh fish, but discerning the quality of seafood is tricky if you’re not an experienced fishmonger.

However, there are some common mistakes you can avoid. Per Joe Gurrera, fishmonger and owner of Citarella fish shop, be selective with where you source your fish.

Experienced fishmongers and “experts will get their product from the best sources and treat the fish carefully to maintain quality," Gurrera explains. Avoid buying prepackaged fish.

In terms of looks, "the skin should be bright and shiny, and its spots, lines, and markings should be sharp," the fishmonger revealed. "A fresh fish should be firm," said Gurrera

The expert also warns against buying any seafood with a strong fishy odor. As for shellfish, they should either be purchased alive or frozen as they can spoil incredibly fast.

According to Gurrera, "lobsters should be moving when you buy them". It's also best to cook them on the same day you buy them for maximum freshness.

"Clams, oysters, mussels, etcetera should be alive when you buy them," the fishmonger revealed. Simply tap on the shell; if the shell shuts tight, the mollusk is alive.