English Koi are a popular species of ornamental fish that are often kept in outdoor ponds. They are known for their vibrant and varied colours, as well as their graceful movements in the water. English Koi are typically smaller than other types of koi, and can grow up to 3 feet in length. They come in a variety of colours, including white, black, red, yellow, and blue, and can have distinctive patterns such as spots, stripes, or splotches.