Out of all of the counters at the grocery store, the seafood counter may be the most unpredictable. Sometimes they simply don't have the fish you're looking for, or the one you want doesn't look too fresh. Knowing which fish to substitute can be tricky, but Epicurious has a whole slew of seafood swaps to help you out. Photo by Ján Sokoly.
Click the link below for the entire list (and other helpful tips), but we'll cover some of the most popular fish here real quick:
Cod substitutes: Haddock, Pollack, Black Cod, Stripped Bass, Hake, Mahi Mahi, Grouper
Salmon substitutes: Arctic Char, Ocean Trout, Amber Jack, Mackerel, Wahoo, Striped Bass, Milkfish, Bluefish
Tuna substitutes: Swordfish, Salmon Steaks
It's worth noting that these substitutes can probably work in reverse too; cod can could work in most haddock recipes, and salmon could be subbed for striped bass in a pinch.