Its hard to tell in the video but is it just a bit cloudy or is it fuzzy & cloudy? As its only one eye, I am guessing he may have scraped it on something. Moors are prone to eye injuries as they have poor vision and delicate eyes. If you have detectable nitrites, water changes will be must to get them well under control.
it almost looks like a clear pimple on the eye. Any ideas what coulld have caused the nitrite spike, but the ammonia and nitrates are under control?