white eye

my betta has also gotten a white patch like circle on the LENS of his eye, also my femal bettas, I have heard that this whiteness can be caused by a fungus. A man that raises bettas says that this problem is usually not fatal but it is probably a certain fungus, it can be treated with salt added in the recommended amounts, or by a fungus away type of cure. So far the salt has yet to help the cloudyness of the eye, however I have not tried the fungus away tabs yet. My male bettas eyes seemed to clear up when I placed him in tetracycline, I dont know why b/c the box does not list this as one of the ailments that it treats, by anywho it went away, but when I put him in a tank with filtration he again developed the cloudy hazy lens that has plagued all my bettas.
OR
I think if the fish is malnourished the eye will tend to cloud further into the eye past the lens, but I am not sure of this.

Check out the cloudy eye related symptoms in the link below.

http://www.fishyfarmacy.com/fish_diseases/eyes.html

cloudy eyes in fish can have many causes including velvet, Ich, fish tuberculosis, corneal edema, cataracts, nutritional deficiency, bacterial infections, fungus, or on rare occasions digenetic flukes such as Diplostomum. trauma and hereditary factors can also be causative. in the vast majority of cases however, water quality is the issue.