Pop eye symptoms happen from top and bottom to bulge out, this isnt pop-eye....unfortunately, it def looks like drop eye and probably just rubbed his eye against the glass which caused the redness. It's common for Aro's to get this and there's really no valid answer as to why. But it is an environmental issue (doesnt happen in the wild). I had friends to surgery and it somewhat helped, but not 100%. I moved my dropeye to a tank that was covered from all sides to keep him from looking out through the sides and in hopes for a cure. Unfortunately, that didnt work. So, out of frustration I sold the guy. **** happens to the best of us
