Cardinal fish with cloudy eye and nodules on bottom

[Benediikt]

My cardinal fish had one cloudy eye yesterday evening, I checked my water and nitrates were a little elevated so, just to be safe, I did a 50% water change. He was also swimming very close to the bottom so I put him in this tank that is meant for baby fish to avoid him being eaten by my crab.Today his stomach has these bubbles or nodules, they are concerningly large and over the last hour one has fallen of, it can be seen in the picture bottom left. I am very concerned as he is also opening and closing his mouth wide. Andy diagnosis is very appreciated, I already looked through humble.fish.

 

[Jay Hemdal]

My cardinal fish had one cloudy eye yesterday evening, I checked my water and nitrates were a little elevated so, just to be safe, I did a 50% water change. He was also swimming very close to the bottom so I put him in this tank that is meant for baby fish to avoid him being eaten by my crab.Today his stomach has these bubbles or nodules, they are concerningly large and over the last hour one has fallen of, it can be seen in the picture bottom left. I am very concerned as he is also opening and closing his mouth wide. Andy diagnosis is very appreciated, I already looked through humble.fish.

Welcome to Reef2Reef

Do the nodules look like they have gas in them?
This could be gas bubble disease or a gas supersaturation issue.
Could the fish have neuter its eye recently?

Jay Hemdal