This is not a disease, it is most probably cause by change of nature to captive environement which encourage the fish to look side and down rather then up. The 2nd most popular hypothesis is overfeeding. Genetic is the biggest factor in this problem.
Cloudy-eye:
As the name suggested, a film of white convering form over the cornea of the eye due to various reasons. Majority of them are mild and do not need antibiotic. However this condition must be treated seriously as its high morbitidy and possible mortality should condition got worst.