Why is Wal-mart still allowed to sell live, tropical fish? As much as I like shopping at Wal-mart in general, this store does a terrible disservice to the tropical fish industry. Not all Wal-mart stores sell fish, and that's a good thing! As for the ones that do, never once have I've seen a Wal-mart store with healthy looking tropical fish. The employees working the pet area have absolutely no training or knowledge in regards to fish.
When buying fish, it's always good to make sure the type you're buying are compatible with the fish in the tank where you plan to put these new fish. A good pet store, or even an average one for that matter, will have general knowledge of fish compatibility. Good luck getting any type of answers when at Wal-mart.
For the sake of your tanks, you're betting off avoiding the purchase of fish at Wal-mart or any other pet store where the fish look sickly or the staff has very little knowledge about caring for fish. Bringing a sick fish home to an already established tank can be hazardous to your current fish. Introducing new fish could mean introducing new diseases and killing the fish you already have.