What is it?
Cloudy eye, like many so-called fish diseases, is not necessarily a disease on its own. There is no one definite cause for it and thus no definite cure. However, despite the lack of valuable information on Cloudy Eye out there it is possible to state this: The majority of cases are caused by (yes, you guessed it!) poor water quality. Excellent water quality is a must, I can’t stress that enough.

If your water quality is great, and you know that for sure, then the second most likely cause is physical injury. If this is the case and it is not infected it should clear up on its own within a week. This is common with new fish in an aquarium, or fighting with other aquarium mates.

If it is not clearing up, then it could be the dreaded bacterial or parasitic infection. Luckily infections if caught early are fairly easy to treat. Infections often occur in bad water… so be sure all your water parameters are great!

There are other less likely causes such as poor nutrition, cataracts, poisoning, or ever just old age! It can also be a symptom of much worse diseases that affect the immune system and internal organs, however it is best to treat it as simply cloudy eye to begin with.

In the long term cloudy eye can cause nervous system disorders and blindness if not treated successfully.

Cloudy eye is especially prevalent in live-bearers and tropicals.

Symptoms:
The Symptoms are quite obvious and easy to diagnose. One or both eyes become cloudy like cataracts. It resembles a white or grey powder covering the eyes. If one eye becomes cloudy it usually indicates physical damage. If both are cloudy it is usually poor water quality, an infection of some sort or a sign of something worse. Other signs include being generally off colour, lethargy or appear distressed.

Cure:
Obviously the first step to curing the disease is to check all water parameters and make sure the water is in absolute excellent condition. Test for ammonia, nitrites and nitrates. Perform water changes to be on the safe side. Make sure there is no foreign substances entering the aquarium that shouldn't be (such as cleaning agents, insect sprays etc.) Make sure the filter is running effectively and change sponges etc regularly.

After you are sure the aquarium is the healthiest it could possibly be and the fish is not recovering it is time to use a treatment. Aquarium salt is extremely helpful with this disease, as it eases stress and prevents re-infection.

Also make sure the fish is healthy and eating well and eating what its particular species requires.

In addition, using an commercial anti bacterial medication will help if the fish has an infection. However wait a week before commencing this to ensure it was not poor water quality or a nutritional deficiency.

Remember, water quality is always extremely important- so always check that first as it is often the cause of disease in aquarium fish. When treating sick fish, try to put the least amount of stress on them as possible, as stress will hinder the heeling process. Another thing is to remember is that generally, a healthy fish is a happy fish.