Pneumocystectomy in a Midas cichlid

A pet Midas cichlid with a 2-year history of a distended abdomen and inadequate buoyancy control was found, radiographically, to have an abnormally large swim bladder. A recirculating anesthesic machine was constructed, and the fish was anesthetized with tricaine methanesulfonate prior to removing a portion of the swim bladder. The entire procedure lasted 71 minutes. Buoyancy problems in pet fishes are common. Causes include subcutaneous air accumulation, infectious disease of the swim bladder inner ear disease, and gastroenteritis. Reduction of the volume of the swim bladder improved this fish's ability to maintain a normal posture in the aquarium.