【How-to】How much does it cost to build a koi pond

As with any backyard pond, a pond dedicated to keeping colorful Koi, can be a great way to keep fish. Ponds not only provide large habitats for your fish, but are also a pretty and relaxing spot for you in your yard. … Koi can live in excess of 100 years, but typically, if well cared for, live 20-30 years.