Tessellating Fish Blanket

I've found a new project! Yes, I know I have a bunch of unfinished projects but this one is cool. It's a fish blanket, here is a photo and here is another. I spent hours figuring out the pattern today from looking at the photo of the finished blanket before stumbling upon the first link. Even though I think this would be an excellent stash project I think I want to do it in two colors - I'm just not sure which ones. Off to start my first fish!