However, before you jump into all these, certain things have to be prepared because basically the breeding pond will actually become the nursing home for the young koi to grow and develop from there. Based on my own experience, usually indoor breeding ponds are more suitable than those placed outdoors because the water temperature are easier to control and not subjected to extreme weather change. In terms of cleanliness, this will also be easier to maintain and in fact the best setup should be an indoor pond with skylight roofing so that the young fry is not void of natural sunlight.
First thing first, make sure that you get the necessary pond supplies for your breeding pond. A polyethylene stock watering tank will make a perfect setup and make sure you get the largest size possible with space availability and budget limitation put into consideration. These specially made show tanks are not necessarily available in pet stores, because I’ve even come across livestock or farm supply stores selling it as well. Moving on to the next step, you will need something that will get the male and female koi to start mating. While most people will prefer breeding mops, somehow for me, I would still go for real live plants instead because what I’ve found is that the koi fry will love grazing on the plant surface pinching out foods from there.
Other than that, make sure that the tank comes along with a pond filter installed and after the fry has hatched, you should consider switching to air pump instead and bring down water turbulence. If you do it right, the process on breeding koi fish should be a routine at your fingertips.
Related topic: Koi Health Problems