Again that is rare to produce hybrids in same pond if the adults are left in the pond.You can keep koi and goldfish in the same pond. However, if you plan on breeding the fish, you shouldn't mix the two together. They will produce hybrids.
Koi and comets frequently produce hybrids when kept together. With flock spawning, you never know what you are going to get.Again that is rare to produce hybrids in same pond if the adults are left in the pond.
If they are that common, why don't we see these hybrids for sale? (I'm awared that hybrids has offered for sale but good luck finding them!). As I said before it's rare to get a hybrid out of them if the adults are not removing from the ponds. Serious breeders only selected the high quality koi and let them spawn in their own pond then remove them from the pond to prevent the adults eating the eggs.Koi and comets frequently produce hybrids when kept together. With flock spawning, you never know what you are going to get.