You have to be careful when buying fresh fish other than shrimp. We bought "scallops" once and they were not scallops. We've been going down for 35 years. The first ten years we just bought from anyone who had a good price. Then I started buying from one vendor who gave me good prices and good shrimp. BTW I buy about 100lbs of shrimp from October to February so I spend a LOT of money. After about 5 years of buying from one vendor, I got a batch of "rubber" shrimp. The next time I saw him I told him if he sold me one more batch of "rubber" shrimp I would find another vendor. Of course, when I was throwing a big Christmas buffet, and no one was eating the shrimp, I discovered it was once again "rubber".
About ten years ago I discovered Alberto & Jessie. They are on the opposite side of the main fish market, across from Mary's. I have never had even one bad shrimp. I have bought his fish and it is delicious. I go to see him a few days before I'm ready to buy and I give him my order which is usually thirty pounds. He has it ready with plenty of ice for my cooler. I have referred many people to him and they love him. He's (Jessie) is a great guy. Tell him you know the Americans who used to have the big blue truck and buy lots of shrimp from him and you expect a discount. He's a pretty big guy so you can't miss him.