How to detect a bad swim bladder

In this video you will notice that one of the Blue Acei cichlids has a damaged swim bladder and can't control it's ability to swim properly. In this case, it stays mostly in a vertical position when not moving forward. It was unfortunately dropped by the girl netting the fish at the store, and when I got it home in the tank I noticed it's injury. Typically this isn't curable and I returned the fish to the store for a healthy one