It depends on what nutrients you are looking for.

Sockeye salmon has the mot astaxanthin, cholesteral,and vitamin D by far because of there unusual diet of almost exclusively plankton. Their unique eating habits make them extraordinary difficult to farm, so sockeye salmon is basically always wild. Also high in omega-3 sockeye has a strong flavour.

Chinook (Spring) salmon has nearly twice as much omega-3 as any other salmon species. Chinooks favor deep cold water. The extra omega-3 keeps them warm and the fat stay liquid in their system and prevents them from freezing. Unlike sockeye salmon chinook can be farmed.

Coho salmon is another strong option. It has the 3rd highest fat content of salmon. Coho has respectable vitamin D content and a solid dose of omega-3.

Pink salmon may be the smallest in size but what it lacks in size it make up for in sheer abundance. With a mild flavour and tender delicate flakes pink are a staple source of nutrients with it’s omega-3 and protein for many.

Sockeye, Chinook, Coho, or Pink Salmon are all excellent choices, each has a specific taste. Try them all to find your favorite.