Wholesale seafood market with many many different seafood(some you will never see in sg)/buy fresh seafood especially sashimi and bring it to a restaurant to be cooked/remember to bargain(be firm)/remember to check the price with the restaurant before giving them your seafood (Noryangjin Station, exit 1)
They have a large variety of live seafood! Ranging from stingrays to octopus and other crustaceans. You name it they have it! The fish market is similar to that of Tsukiji Fish Market in Tokyo, other than it being slightly smellier and lacking in the hygiene area as compared to that of Japan. You can purchase the seafood on the spot and bring it up to any restaurants at level 2, where you can have it cooked or not cooked in any ways you desire!