Help my eel is dying!

my ribbon eel looks horrible, looks like he will be dying soon.

he has some discoloration towards the end of his body, kind of looks like see through, as well as a rotting, mucusy look. he's breathing very rapidly, and isnt eating or moving very much.

will someone please tell me what is wrong asap.

thanks in advance

 

What are your parameters?

 

What color is it? is it turning green?

 

the parameters are stable... maybe just high nitrates. but i've had him in this tank for over a year with high nitrates, and he's been fine.

 

the color is grey-ish white. not green

 

oh okay..i was just curious because from what i have heard..ribbon eels go from black..to blue..to green throughout their life..and when they turn green it means they're about to go..

may be wrong though..

 

ah ok, i think its fin rot, though honestly, i will keep on looking