Hole-in-the-Head Disease
Drs. Foster & Smith Educational Staff

About Hole-in-the-Head Disease

Although the name may sound humorous, the disease is serious. Primarily affecting cichlids and also known as Head and Lateral Line Erosion (HLLE) or Hexamitiasis, this condition is still poorly understood. Many believe the causes are poor water quality and a lack of vitamins A and C. In most cases, the etiology (cause) is probably an internal normally harmless parasite, Hexamita, which lives in the fish's stomach. The hallmark of this disease is erosion of the pores along the front and side of the head. This does not always happen and many authorities believe almost all aquarium cichlids are affected to some degree with Hexamitiasis and readily transmit the disease to each other.

It is believed that when the cichlids are stressed and weakened from vitamin deficiencies, poor quality food, and/or poor water quality or other stressors, the Hexamita migrate through the fish's system. The sensory pores (on the front and the side of the head) become pus-filled if the microbes migrate to these locations. If the parasite invades a vital organ, death follows. Since the fish's immune system is already compromised by the Hexamitiasis, serious illness may also result from the secondary invasion of bacteria or other parasites.

Treatment is only conditionally effective using metronidazole. It is very important to treat all cichlids from an infected aquarium whether or not all are showing outwards signs or symptoms. Choose a medication such as Hex-A-Vital or Metro+. Follow label directions carefully and provide fish with a stress-free environment, high quality food, and vitamin supplementation to help increase the fishes' appetites.