Red striped cardinalfish breeding or sick?

[Fritz05]

I have three red-striped cardinals (Ostorhinchus margaritophorus) in my 65g. This morning one suddenly showed an impressive bulge underneath the mouth. My first thought was a disease, but then I remembered they are mouth breeders. Can anyone tell me if this looks like the fish having eggs in the mouth? It behaves normally, I did not check if it was feeding.

 

[Jay Hemdal Verified Community Expert]

I have three red-striped cardinals (Ostorhinchus margaritophorus) in my 65g. This morning one suddenly showed an impressive bulge underneath the mouth. My first thought was a disease, but then I remembered they are mouth breeders. Can anyone tell me if this looks like the fish having eggs in the mouth? It behaves normally, I did not check if it was feeding.

Your fish looks like it is holding eggs. If it showed like this overnight, then that is surely what it is. The only disease that causes this is goiter, and that takes weeks or more likely months to develop.

 

[Fritz05]

Thank you for the fast reply, Jay. Have a nice say.