something seems to be wrong with one of the two white clouds I added to my shoal of five.
The male is hiding behind the plants instead of schooling with the others, is emaciated and has a right fin that sticks out permanently. The area around the stiff fin is whitish and swollen. His body also looks very slightly lumpy. The other fish (6 panda cories, 4 rosy red minnows, the other white clouds) show no sign of illness and are their usual selves. Does anyone know what could be wrong with this fish?

Thanks!