Shiro Bekko are koi with a solid white body and areas of black pattern appearing on top of the white. As with all Bekko koi, the black appears mainly above the lateral line, with very little or no black wrapping around to the bottom half of the koi, below the lateral line.
Shiro Bekko are a derivative of Sanke. Basically, they are Sanke with the red removed. Scaled Shiro Bekko will have a flat, matte-white base color. However, you will occasionally see Doitsu Shiro Bekko with a metallic white base color, similar to the white found in Platinum Ogon.
What To Look For
The white base color of Shiro Bekko should be as close to pure white as possible, with no yellowing or other flaws to the color. The head of Shiro Bekko typically do not display any black, and should be solid white with no blemishes. A cloudy head on a young Shiro Bekko may or may not clear up with age, there is no definitive way to tell.
The black should be similar to that of Sanke, with a deep, consistent color across the entire body. The black should be moderate and balanced along the body. Since the pattern is a very simple two colors, too much or too little black, or black confined to one end or side of the body will detract greatly from the beauty of the koi. The edges between the black and white should be sharp and well defined. Avoid any young Shiro Bekko with blurred edges to the black, as this will only become more apparent with age.
Remember, even the slightest hint of red on the body, head or lips makes the koi a Sanke, not a Shiro Bekko.