Anybody wanting a real bargain in fresh seafood should try Yang Tse butcher shop/fish store on Mission south of 16th. st. They have exemplary fresh fish: salmon - $3.99#, nice big prawns - $5.50#, trout - $2.50#
I have no personal or business connection.
What I've been doing is getting about 3 pounds of shrimp home and steaming them pronto without cleaning them.
Then I take them out of the fridge and clean as needed over like the next 4 days, no problemo on the freshness.