Outdoor Pond --- what to do with my KOI???

[BMW Rider]

I have a 60 gallon tank that I winter my pond fish in. My pond is too shallow as well to keep overwinter. The tank sits in my breakfast nook, and its kind of nice having the fish there to watch during the winter months. I don't have any koi though, just pond comets. My pond is a bit small to keep koi as they mature. I just run the tank on a Fluval 403 filter and a small air pump. Has kept them alive for 4 winters that way. I even built a new stand for it last year so it looks a bit nicer now.