Hi Koimystic
My name is Chris du Plessis and a breeder of nishikigoi in South Africa.
And like to help you where I can, so if you whant to do breed with koi you must first decide the variety and then you must look for good blood lines,and you must not try and mix difirant veriety's it will always come to a disaster.
You will see that it will take years to get the right pair of parents.Specialy with kohaku's see if you get them with good HI and the white is also important but the most important aspect is the body shape and look at their head matching with the body it's very important.You will see with in a three weeks the fry showing if you was sucsessful or not and the most of the fry will be completely covert with HI and that means that the parents did not match and you must look for another male or female .And thats the same with the other veriety's and you must keep on trying it will payoff one day and thats the fun of it. If you need more exsplination please let me here from you and I will help you where it is posible.
Regards
Chriskoi