Ah Vietnamese farm raised catfish, also known as swai, pangasius, or basa. It's a decent, mild fleshed fish, but very different from the somewhat pricier American farm raised channel cats. There are a lot of places that sell this less costly fish under a more well known name, often grouper, which is ridiculous. If you are eating a grouper sandwich somewhere that only costs $8.99 it either isn't grouper or the restaurant is losing money. Sorry for the rant