Yes they spawn when it starts to warm up during full moons and a bubbler helps other then that I say try being lucky u can raise a egg to adult if u don't have old enuf koi female 4 years male 2 years great water quality and when it happens u might miss it and all the eggs get eaten before u get to them and never know they have been spawning other then that luck money time energy i def understand y a beautiful small fish can be so pricey Some ppl say they spawn every season except winter here in louisiana I can see that being true hope this helps I'm sure somebody else will chime in with better advice