The restaurants are usually open around the evening – but the fresh(est) seafood actually arrives into the square early early morning. You’ll find it busiest from like 2am to 5am on weekends – lots of people go there after clubs/KTV/whatever. I think the crates of shrimp arrive at like 3am.. you can go buy your seafood in the ‘warehouse’ of seafood and bring it to a shop to cook up how you like if you don’t want to pick from what they have, also.