With over 30 temporary tanks set up in the parking lot of Wyndham Garden Silicon Valley Hotel, visitors Saturday gazed over the top of championship-caliber koi. Some of the competition fish showcase the most traditional and prized colors in koi, like deep orange, red, black, and iridescent white, layered in among the smooth scales so intricately they resemble marble. Other koi are one solid shade of bright golden yellow, bronze, pastel salmon, or grayish black