Starting a Koi pond will take time, work, and money, but it can be very rewarding. Here's what to consider before you get started.
As with any backyard pond, a pond dedicated to keeping colourful 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. Ponds, though, are very different from aquariums, and as such, require much different care and maintenance. Furthermore, Koi fish, though hardy and easy to keep, require some unique considerations. Before starting a Koi pond, you should know what you're getting into.
Koi fish can be very expensive. The more expensive fish are valued for their marking and lack of defects. Roughly, 1 in 5,000 Koi achieve the highest rank of Premium. Their size is also an element in their value. Koi can live in excess of 100 years, but typically, if well cared for, live 20-30 years. The fish will continue to grow throughout the span of their life, so it is only those older, larger, most beautiful fish that fetch the sums in the thousands. Koi demand a large environment, and this can cost a great deal as well. Generally, the ideal size for a Koi pond is considered to be over 1,000 gallons and at least three feet deep.
Koi fish need a lot of space. How big exactly is 1,000 gallons? Well, at three feet deep, a six foot by eight foot pond will yield 1077 gallons. But these are merely the minimum recommended requirements. Also, the more fish you have, the larger your pond should be. A pond of the aforementioned size will be enough for no more than five average sized Koi. More Koi necessitates a larger pond. If you plan on having fifteen Koi, you will need a pond with roughly 3,200 gallons!
Though Koi are very hardy fish, you will still have to provide them with adequate equipment to keep them healthy.
One thing to consider is the climate. In a three foot deep pond, Koi can survive about six inches of surface ice, but the pond needs to retain contact between air and water. This can be achieved with a bubbler or de-icer. Also, a fountain or waterfall is a good idea to increase aeration in the water.
Your pond will also need proper filtration, including biological and mechanical filters. A bottom drain is also a good idea, as it will help with water changes. Pond water maintenance is as important as aquarium water maintenance.
Koi are also very susceptible to outside predators. Consider some sort of defence system, such as netting or electric fencing.