Thanks for your help. Let's hope it isn't total blindness.I had him about a year and half after he went blind. Lost him due to my own stupidity forgetting to plug my ato in for a week. Just make sure he's getting food. Mine figured out the spot where floating pellets gathered and would get a few that way but not a ton. The solo cup a couple times a week ensured he got decent meals.
He was weaker than the others but adapted to a degree.