Your fish are NOT healthy in any way shape or form. You do not clean your tanks and you treat the fish with zero respect. You need to start conducting more water changes and clean your filtration system more as well as the tanks. You also need to be truthful to your customers among compatability and gain some knowledge before you buy certain fish wholesale. Customers/hobbyists work for a living and they don't need to keep coming back and buying more fish that are going to die from poor maintainance.