sick ghost knife

[lordpet]

Hello

Today I was feeding the fish and noticed the ghost knife is lying more or less on its side, long white patches along the body. He's swimming pretty weakly.
I was thinking ich but it doesn't look like salt, rather long.

Sorry for the photo orientation.

What is it and is there anything that can be done?

 

[lordpet]

I got him out of the tank and he's looking mangled, fins all torn up. Could he have been wrecked by a pleco or some other fish?

Actually, now he's dead. What the hell?

 

[lordpet]

Here is mangled ghost knife fish