Although bettas are often marketed as no-maintenance pets or as decorations, they require attentive care and clean water like all other fish. Popeye disease is named for its tendency to cause the eyes to bulge out of the head and is usually the result of poor husbandry.
About Popeye Disease
Popeye disease causes one or both eyes to become grotesquely swollen. The eye may look like it's bulging out of the head. With proper care, your betta may be able to make a full recovery, so if you notice symptoms of popeye disease, consult a veterinarian immediately. Left untreated, the disease can result in massive infection and a painful death.
Popeye Disease Causes
Popeye disease is usually caused by a bacterial infection in the eye. The most common cause of such infections is dirty water. Bettas are often sold in small containers that quickly become dirty and infected with bacteria. They can transmit the infection to other bettas. Occasionally, however, tuberculosis and other serious medical conditions can cause popeye. In these cases, popeye is more difficult to treat.
Popeye Disease Treatment
Because popeye is caused by a bacterial infection, your betta may need antibiotic treatment to recover from the illness. Your veterinarian will ask you questions about your fish's habitat and determine whether the popeye is a result of a bacterial infection in the eye or a more serious underlying medical condition. Because it is often difficult to find a qualified fish veterinarian, you may need to try treating the infection yourself. Administer an antibiotic treatment directly to the water, carefully following the package instructions.
Popeye Disease Prevention
Quarantine new fish away from other fish for at least seven days to prevent the spread of bacterial infections. It's also vitally important to keep your betta's water clean. Bettas need, at minimum, one gallon of water per fish. Change the water weekly and ensure your pet has sufficient oxygen by adding an air stone or live plant. For larger tanks, use a water filter and change the filter cartridge according to the package instructions or monthly.