Yellow is a very difficult color to accomplish in koi. It usually becomes orangish. A pale pumpkin orange is considered pretty good for Ki Utsuri, but is not a pure yellow. Young Ki Utsuri can have a decent yellow, although usually it is muddled with grayish undertones. As they mature, the orange creeps in. The best yellows are found in Yamabuki and Hariwake... red has been difficult to establish in the metallics. Yellow has been able to remain pure in them, albeit marred by orange specks oftentimes. (The red Kujaku is fairly unusual, but can be found.) The red-eyed Kigoi gives a great yellow, but it is due to a form of albinism that inherently cannot be transferred into Utsuri. An occasional koi will have yellow as a passing stage; and rarities, like the 'yellow Shusui' always draw attention. If a deep, pure yellow is created in Showa, I think it would be a knock-out. Maybe it will happen someday. An orange Showa is just a Showa lacking the intensity we have come to expect of the variety. But a true yellow etched with lacquer black against white would have a brightness quite different from the drama of Showa.
Good luck with your ol' yeller one.
