If you’ve ever woken up to your Siamese fighting fish staring at you with googly eyes, you’re not alone. Congratulations. Your Betta fish has something known as exophthalmos, also known as Popeye. And the new googly eyes your betta is sporting are a symptom of two possible problems:

• mycobacterial infection (which is easily treatable)
• tuberculosis (not so treatable)
• parasitic infection
• Ichthyophonus or Ick (another bacterial infection and highly treatable)
• eye flukes
• internal metabolic disorders

Either way, the reason your betta’s eyes bulge is because there is likely an abscess behind the eye.

How to Treat Popeye on Betta Fish

If the cause of Popeye is a mycobacterial infection, you should go ahead and treat the root of the bacteria first. This is easily done by cleaning the tank water and making sure the pH balance of the water is slightly acidic. As a side note, almost all bacterial infections found in bettas and other pet fish can be prevented or at least reduced the risk of their occurrence by keeping the water clean and controlling the pH balance.

Additionally, you can treat the water with tetracycline or terramycin, two very popular antibacterial medications that you can buy at your local pet store. The standard is to add this to the water… 100 mg of the antibiotic per 4 oz. of food.

If this doesn’t work, you can try these other methods for a quick fix that also work well as a preventative measure for your betta…

• Heat the water to 86 degrees. You’ll want to do this gradually at a rate of 1 degree per hour. The water temperature should already be in the high 70 degree range.
• Add a little salt to the water. The key is “little”. Do not give your betta fish a salt bath. The percentage of salt added to the water must not exceed 0.6%.

Both of these quick fixes will help keep bacterial infections at bay. It is important to note that if your solution shows signs of Popeye, you should avoid contact. Although your betta is unlikely to have tuberculosis, it is transmissible to humans through open sores.

In conclusion, Popeye is treatable and, like most bacterial infections, the cause is usually dirty water or low pH. The best way to prevent Popeye is to make sure your betta fish is in a stress-free environment. That means clean water, good food, and nice, warm water.