A good koi pond design will consider a variety of different factors, including aesthetic appearance, good filtration, ease of maintenance and of course, ensuring that your pond is fit to support life and keep your koi healthy.
The exact design of your pond is a matter of personal choice, but ensuring that you account for all of these factors should be your main priority. Before thinking about how to build a koi pond, first check out our article on koi carp pond design for guidance on planning your pond.
Once you know what you want from your design then you can get started with the fun part: building your pond! Below, we explain the step-by-step process of building a koi pond…
How to build a koi pond:
- Use string and sticks to lay out the perimeter of your pond and to give you a pattern for digging your hole.
- Get digging! While you can of course dig your koi pond by hand, your pond will almost certainly be large, and in places, deep, so you might want to hire a machine to help you to excavate your hole.
- Smooth off the design, making slopes steady and smooth, and ensuring that the earth is compact and stable.
- Remove any rocks or sharp implements that might damage your pond liner.
- Place and install any piping, drains or filters that you might want in the base of your pond, ensuring that the ground tapers to allow the pond to drain or cycle through any fittings you put in.
- Cover the base of the pond with a protective layer, such as old carpet, to provide an extra layer of strength and security for your liner and avoid leaks.
- Measure the pond for the liner, ensuring that you allow a generous margin of at least two feet on the edges, plus extra for any mistakes!
- When you are ready to place your liner, lay it out next to the pond while folded up, and unfold it into the hole carefully and gradually, ensuring that it is firmly pressed into crevices and graduations to make a good fit.
- Smooth the liner out within the hole, enduring plenty of slack and a generous border over all sides of the pond. Remember that the water will push the liner firmly into any gaps, and shrink your margins, so never trim the liner until your pond is full of water!
- Once you are confident in the position of your liner, cut out holes for the filters, drains and skimmers in the base of the pond. Seal over the holes once you have pulled all of the equipment through, ensure they are watertight, and leave them time to cure.
- When you are ready to fill your pond with water, try to use a metered source so that you know exactly what volume of water your pond holds. This will help you with later calculations on fish stock and water levels.
- Manually work out any creases in the liner as the pond fills.
- Once the pond is full and has had time to settle, you can now trim down your liner (if needed) and bury the edges. Alternatively, build over the edges to provide a border to the pond.
- Complete the installation of your pumps, aeration, filters and piping, and check that they are all working.
- Check for leaks, problems and soft spots in the pond’s liner, and keep the pond watered and all of the equipment running for several days to ensure that everything is working as it should.
- Add any water treatment agents you might need to your pond, and allow at least 2-4 weeks for the pond to fully settle in and reach ambient temperature before you consider adding your first plants and fish.