Hello,
I know exactly what this is and i hope the information below helps you understand what/how to help your fish.
P.S = Yes your fish can catch this; if you do not make changes to your fish tank, all your fish mat catch this disease.
P.S+ = This cloudy eye as i am telling you below it can develop into one pupil being bigger than the other, so use the information below to help you sort this out.
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DISEASE AND CAUSE: Cloudy eye. Caused by poor water quality, poor diet, eye flukes, corneal damage, bacterial infection.
SYMPTOMS: Entire surface or lens of eye takes on a cloudy, opaque appearance. There may be a build-up of mucus on the outer surface.
REASON FOR INFECTION: Most commonly caused by poor water conditions. A lack of vitamins in the diet may also cause clouding. On rare occasions digenetic flukes, such as Diplostomum, can cause problems.
ACTION: Improve water conditions. Use a good quality food containing added vitamins.
TREATMENT: Improving water conditions usually cures cloudy eyes. Eye flukes are uncommon and can be difficult to accurately diagnose and treat.
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Hope This Helped You, And The Best Of Luck To You,

!