Pond Design: How to Design a Koi Pond

While keeping koi carp doesn’t have to be difficult, getting the design of your pond right and ensuring that it is suitable for koi is really important. There is much more to building a good koi pond than simply digging a hole in the ground and filling it with water!

However you wish to set up your pond, however many fish you intend to keep and however much space you have available, there are several common elements of pond design that you should always consider in order to ensure that your eventual koi pond is suitable for your fish.

In this article, we will explain the key elements of pond design and help you to ensure that your koi pond can adequately provide for the needs of your fish.

Koi pond surface area

The surface area of your koi pond will need to be fairly large in order to provide enough oxygenation and allow your fish room to grow. Aim for as large a surface area as possible, and 100 square feet as a minimum.

Water volume required for koi carp

You should ensure that the total water volume of your pond is not less than 1,000 gallons at an absolute minimum.

Koi pond design: a waterfall flowing into a koi pondDeep and shallow areas

Your koi pond should not be a uniform depth; the base of the pond should be graduated, creating deeper and shallow areas. Provide at least one deep area of 6 feet or more, and some shallows of not less than 2-3 feet deep.


Ensure that you have adequate provision for plumbing lines and getting water to your pond; you will need flexible hoses, access to a tap, and easy access to all of the pond’s plumbing in case of any problems.

Water movement

You should provide at least two water pumps at different points in the pond, to keep water circulating. Ensure that there are no dead spots of stagnant water. Air stones and other equipment to provide oxygenation to the deeper levels of the pond are also essential.

Algae control

You may wish to install a UV sterilizer in order to keep the growth of algae, plankton and bacteria under control, as micro-organisms will thrive in the pond environment on the waste generated by your fish.


Depending on the climate in which you live, you may need to make provision to heat your pond during the colder months. While koi carp are coldwater fish, they will not thrive in extended periods of bitterly cold weather, so take this into account.


Filtration is vitally important for koi carp, as they generate a lot of waste! As well as planting plenty of koi-suitable plants to help to filter waste and maintain the water quality, you will also need to account for manual filtration, such as by using a gravity-fed filter system, bead filters, and biological filtration.