Carp farming in Koriyama begins with a water project. In the Meiji years a channel was cut to bring water down from Lake Inawashiro, and it was in the irrigation ponds of that system that former samurai families started raising carp.

A second condition made it work. This was silk country, and silkworm pupae, which carp will eat, were readily available. Water and feed together, and the production grew from there.

Carp raised on water off Inawashiro is described as carrying little of the muddiness people associate with the fish, and it is shipped out of the prefecture to Yamagata, Akita, and Nagano.

For kanroni the fish is simmered long and sweet, with sugar, starch syrup, soy sauce, and sake, until the smell is gone entirely and what remains is savor. The instruction people give is to leave it overnight and warm it through the next day, when the flavor has gone further in. It used to be food for occasions. Now it is eaten all year and served in restaurants and inns. The transmission area listed for the dish is Aizu, further west, which is a reminder that a food and the industry behind it do not always sit in the same place. A nineteenth-century engineering scheme to move water across a plateau ends, three generations later, on a plate.