1 Depth is important

Depth of your pond is crucial. The minimum recommended depth is 4 feet, however
it is much better to give your fish six or even 8 feet deep pond. This will
ensure that your koi are protected from raccoons, cats and other animals who
love a fish dinner. Deeper fish pond also helps to keep water cool in hot summer
days

2 Make your pond as large as you can

Small ponds are not suitable for koi. Remember, with time koi can grow quite
large and they will need a lot of room. Also there are so many color variations
of koi, that with time you will probably want to add more fish to your pond.
So it is better to create a large pond from the start than rebuild it later.
About ten thousand gallons is a good size for a koi pond, bigger would be even
better.

3 Use fish pond heater in colder months

Unlike tropical fish, koi don't suffer much from cold; however you should never
let your pond freeze completely. Installing a proper pond heater will always
keep an opening in the ice. Also keep in mind, that koi only grow when the water
is warm, so with a heater your fish will grow faster

4 Plan some shade for your koi

When selecting a spot for your pond, make sure it is out of direct sunlight.
Also keeping water plants like water lilies in your pond are a good idea - not
only they add beauty to the overall design, but they also provide shade for
the fish. However, you should avoid building your koi pond under trees. Cleaning
a fish pond of fallen leaves is no fun.

5 Plan to install a bird net

There are many birds of prey that would love to steal your koi. Don't give
them the opportunity; plan your pond location so it is possible to cover it
with a net.

6 Keep insecticides away from your pond

When landscaping your pond keep in mind that you should not use any insecticides
or herbicides near the water. Even a small amount of common garden poison can
kill your beautiful fish.

7 Get proper equipment for your pond

Several accessories are absolutely essential for a healthy koi pond. Ideally
you will have to invest into a water pump, filtration system, water aerator
and an ultraviolet sterilizer. If the water in your pond is still, your fish
might get sick and eventually die. Koi pond filtration systems are expensive,
so as an alternative you can make your own homemade filters.