Well, this is a true freshwater Goby, so salinity shouldn't be anything to even consider.
As far as I know, all gobies have cloudy eyes. I've seen it to varying degrees, though, and thought I could do something for him. This species, Mogurnda Mogurnda, is not a picky fish, so I'm not concerned for his health, here. The first day in the 55, he hid for five minutes and then took to hunting. He's picked off a fair number of guppy fry and he's eating any pellet I've tried. He's in great health. This is not a subject for the Disease forum, but I don't want to step on toes.
This is really more of me looking for the known, common reasons. Somebody moved this post away from the Characin page where somebody might have been able to help. I don't want to lock horns with the likes of whoever that was, so I'll just keep bumping this here until somebody knows.