Glass Cardinal - Problems?

[GoFish]

I have 3 Glass Cardinals. They school together, eat together and have perhaps problems together?

Fins:
1. pieces of their fins go missing... then grow back
2. pieces of their fins go white... then it disappears
3. Pieces of their fins look like they're eroding... then grow back
4. the soft tissue between the tiny bones in their fins separates... then they grow back together

Skin:
1. sometimes white fleshy sores appear on their sides... then next week they're healed and fine

And finally, one of them in particular over the last month has developed a LARGE CHIN. The first time it happened for 3 days, then again it happend for 4 days. During this large chin phase it doesn't eat, it chases food like its going to eat it but then just watches it fall??? The other 2 eat just fine.

An ideas or advice? Discuss? I keep thinking about posting as i haven't found any info searching