Killifish in an outdoor koi pond?

[two_wheeled]

Question about killifish. My interest was piqued last year when a local aquarium enthusiast suggested I put flag fish in my backyard koi pond (3000 gallons). I always have lots of Gambusia / mosquito fish in there, but they're small and dark and boring. I've been wondering ever since, could killifish live and breed in this environment?
My water ph is always stable at 8.0. Water temperature hits a high of 85F in the summers and a low of 45-50F in the winter (I'm in Arizona), but I also have an outdoor heated tank that they could be moved into over the winter if that's too cold.
If not killifish, maybe something similar?
Appreciate any feedback. Thanks!

 

[Archerfish]

Keeping American Flag Fish with Koi is done here in Florida. The breeders keep them to help control algae. So they are compatible. The question is how will you recover them in the winter from a 3000 gallon pond? 45 degrees is pretty cool for those fish. Although, they could survive. No idea. I have never kept them in water that cold. Regarding the size, you will see them in the shallows 'grazing' but normally, they will not be constantly visible like top water swimmers or highly visible Koi. I tried some in a pond and really didn't see them very often. They are an amazing fish and so very beautiful when viewed from the side. Good luck!

 

[Back in the fold]

Blue Gularis . I’ve heard stories , many stories , about this difficult to spawn Killifish being raised very successfully outdoors with the added bonus of them reaching very large sizes .