convict goby

My engineer goby is going blind. It started all of a sudden and it’s not effecting my only other fish (a four strip damsel). He’s is literally methuselah. Hes around 18” long in my biocube 32 and that we know of (who knows how old he was when he was bought) he’s 10 (at least, we can’t remember...

My engineer goby just popped out to eat and his eyes are blue. I’ve never noticed this before I’m pretty sure they were black. What does this mean? Is he hurt or sick?

So I have a biocube 32 led with all stock equipment and the following parameters: ammonia-0 ppm Nitrite-0ppm Nitrate - 15 ppm pH-8.0/8.2 (kinda colorblind so cant tell) so I’ve got a massive, and I mean massive, engineer goby named kashima (18-20” long). He’s going on 7/8 years old (my dad got...