I have always wanted KOI, but they can grow to be 3 to 4 feet in length. Not something you want to move every year or so.
A KOI pond will be a must after I get my house, garage, and garden.
When I finally go to Japan. A KOI farm will be one of the many places I want to visit along with local bike shops, seafood market and a traditional tattoo studio for some ink work.
Maybe I can go in a hundred years or so when I will be able to afford it.