Wired stuff on fish help

[asmodyus]

My fish have these large white spotches on his fins any idea?

No other fish in tank seem to have it.

 

[cnreef]

Lymphocystis?

 

[risin]

sand? The fine grains of sand stick to my chalk bass's fins when they have been sitting in their hole. Usually falls off the first time they make a quick movement. Also, they look skinny in those pictures