More and more homeowners are making koi ponds their go-to garden feature. With strategies and equipment to help the fish through the winter, residents find the fish grow and become another family pet.

Florence Danly named the koi that swam in her backyard pond. There was Sky and Bella and Big Mama and Goldie and — her favorite — Marilyn, a large-eyed diva of a fish who liked to flaunt her beautiful ...