Merman!Kurt fic

Hi,

I am looking for a fic that I think was on ff.net?

In it Kurt is a merman, Blaine is human..
A few points I remember.. Kurt gets legs and they're at a market where they see a mermaids fin and Kurt freaks out. Later in the story Kurt is taken and kept prisoner in a tank with not enough salt so he is slowly dieing, I think the story was complete but not sure.

Please and thanks!