Whats up with my FH?

[Vulkan]

Im not sure whats with my RD, but since last week his Kok has shrunk and his stomach deflated, and his fins all crumpled up. He's became less active just hanging in one spot. I moved my other FH to a different tank, his personality seemed to come back but still looks physically in bad shape. thnx in advance

 

[Camphilophus]

Could be internal parasites. Does he have white stringy poop? Try feeding some garlic food. Make sure the water is clear. You could add some epsom salt to clean out the parasites if garlic doesn't fix him back up.

 

[loureyes]