Banggai Cardinal stopped moving, heavy gasping.

[DoINeedAName?]

This morning my Cardinalfish was laying on tank bed, gasping and not moving. Was red under gills earlier, but no red now. All other critters are fine, other Banggai Cardinal is timid, Cardinals are recently added, but otherwise fine. Moved Cardinals to QT tank with only the cardinals, pajama cardinal, four hermits, 3 red leg, 1 blue leg, and a chocolate chip sea star. Well… I was going to post this less than half an hour ago asking for ways to save the fish. He has just died because the hermits were picking at his gills. No clue what killed him though. Like, made him freak and give up basically.

 

[Idoc]

No clue what could have killed him without pics/videos of how he was acting. Now, you will need to watch the other fish very closely for signs of disease or strange behavior.

 

[damsels are not mean]

Sounds like either disease or aggression (cardinals can be vicious to eachother)