Koi fish are among the hardiest of fresh water fish. Originating in Japan and raised by Koi farmers for food. These fish now are bought and sold across the world and bred for their remarkable colors. Some even sell for thousands of dollars.

Although hardy, Koi can at times be weakened by parasites or bacteria. The problem is that there are hundreds of strains of bacteria that can affect these fish. Some fish have resistance to certain strains while others are severely affected by the same. Proper diagnosis is the most important step for the cure. Blue Koi has the experience to diagnose fish upon visual inspection.