Designing a koi pond

Keeping koi is as much a hobby as it is a way of life for koi enthusiasts, and this hinges on the best possible pond design. . Either way you do it, the following need to be considered.

Design considerations

Materials for koi pond designs range from natural ponds to fiber glass tanks, gunite or PVC. The first consideration one must take is to decide where the pond will go. It is recommended that koi ponds are not placed underneath trees (as this will significantly add to your maintenance), but should be placed in a position that sees a balance of sunlight and shade. Experts say that bigger is better when it comes to koi pond designs. A well-designed koi pond usually has a depth of between one and two meters, and can accommodate at least 10 000l of water (users are advised to calculate the amount of koi as one large fish per 1000l of water). The floor of the pond will be sloped to one or more bottom drains.

Technical considerations

Once your design has been decided on, various technical elements need to be considered. Additional considerations and essential equipment for your koi ponds include:

  • Plumbing is vital.
  • A UV Sterilizer to control plankton, algae and bacteria.
  • An air system to maintain adequate oxygen saturation.
  • Three or more jets to re-circulate and exercise the fish (with natural ponds, this can be replaced with a waterfall).
  • At least 1 skimmer dependent on surface area and particulars of the site.
  • One or more bottom drains.
  • An external gravity fed filter system as the foundation of your filtration system.
  • A bead filter to remove small particulate and boost bio filtration.



Clear water doesn’t necessarily mean clean water, and the ammonia and nitrite that builds up can be lethal to your koi fish. To that end, a reliable filtration system (which can be biological, chemical or mechanical) is essential. These filters also need to be cleaned regularly to reduce the sediment build up.

The design and construction of koi ponds is an intricate art, and it is therefore advised that a professional be commissioned for this kind of project. Firstly, the designer needs to understand all the requirements (such as safety and functionality) before building, and it is a specialised construct. In the case of koi, a professional is the best route.


*This article was sponsored by Townhouse Pools

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