I have never seen a healthy looking walmart fish of any species. Except maybe the plecos, just because it's hard to tell. You can just see the sickness in most of their fish.
Never buy fish from a store with unhealthy fish. Even if the ones that are unhealthy are in another tank, the fish you get might not be showing it. Look for any dead fish, fish with ich, or sluggish fish looking literally sick, tails bitten off or fungus growing. Look for overstocking to the extreme too, where the fish can't swim without touching other fish (except in goldfish and feeder fish tanks - though some are known to have diseases from their tight quarters).
As crazy as it sounds, it's usually better to ship fish from a reputable breeder online. They generally breed one type of fish and give them a nutritious diet, house them with appropriate tankmates, and the fish haven't been crowded in a fish store for weeks after being shipped from a wholeseller. The breeders package their fish correctly so it causes the least amount of stress. Fish in the fish store have have weeks of stress, where being shipped, it's usually just 2 days. You can also get prettier, cheaper, and healthier fish by shopping from a breeder AND you are supporting quality captive breeding programs, which is a good thing all around for aquarium fish and the hobbyists!
Ok end of lecture lol not trying to call you out at all, but just have this information here for anyone seeing your thread thinking about buying a walmart fish