Six Important Tips to Create a Koi Pond

Six Important Tips to Create a Koi Pond

Koi, with their colors and drawings, are real gems for the garden pond. However, they make high demands on the care. They need enough space to be able to swim unhindered. They are always hungry and need satiating food. It would help if you remembered that koi could grow old. Before you buy koi, you should consider whether you are ready to care for these exotic beauties for such a long time. If you take the following six tips to heart, you’ll get a lot of enjoyment out of your koi pond.

Preliminary Considerations for Keeping Koi

Koi originated in Asia. With their colors and designs, they enjoy great popularity. Kois has a proud price. It is all the more annoying when the precious fish become ill and die. If kept properly, koi can live to be more than 50 years old. You must be prepared to care for the animals over such a long time. Koi proliferate and can reach up to 3.3 feet (one meter) in length. Therefore, sufficient space is all the more critical. You should only buy koi if there is enough space in your garden for a koi pond. Koi are very demanding in terms of care. You should only keep koi if you are sure that you can put up with this high effort in the long run. Keeping koi involves a lot of work and high costs.

Not to forget is the feeding behavior of the Kois. They are always hungry and eat until there is nothing left. Therefore, you should buy the right food that saturates for a long time.

Koi are social animals. They feel comfortable in a group and can also become very trusting.

1. The Right Size of the Pond

Since koi like to live in groups, you should keep a group with about ten animals. This already indicates how big the pond should be and what water volume is essential. A single fish needs at least 1,300 gallons (5,000 liters) of water. You should calculate with at least 260 gallons (1,000 liters) of water for each additional animal. Therefore, the pond must be correspondingly large for a group of animals. So, for a group of 10 fish, you will need at least 4,000 gallons (15,000 liters) of water.

There are hardly any limits to the size. The larger you can build the pond, the better it is for the fish.

The pond should be at least 5 feet (1.50 meters) deep to give the fish enough room to swim. Even better is a depth of 6.5 feet (2.00 meters). The animals can then also overwinter in the pond without any problems. Koi fit very well into an Asian garden. Therefore, in terms of shape, a simple rectangular pond is suitable. It can be best integrated into a Japanese garden. A size of 20 x 10 feet (6 x 3 meters) is optimal. This corresponds to an area of 200 square feet (18 square meters). At a depth of 5 feet (1.50 meters), your pond will have a volume of 6,600 gallons (25,000 liters).

With a koi pond, you do not have to pay attention to the shore, shallow, and deep water zones. The pond should have the same depth throughout. The pond walls should slope as steeply as possible.

2. The Right Location

Once you have decided how big the koi pond should be, it is crucial to find the right location. Only if you have enough space in your garden and a suitable place should you create a koi pond.

To have as many of your animals as possible, you should choose a place from which you can easily observe the fish. A place in front of a terrace and a sitting area in the garden is well suited.

A location near the house is ideal. You will need the appropriate technology for the pond. So you can easily accommodate the technology in the place and do not have to walk long distances for maintenance.

In Japan, where pangolins originated, ponds are usually designed, which extends into the house. In bad weather and cold, the fish can retreat to this warmer area. This comes at a high cost, as you will have to remodel your house unless you are building new.

If you place the pond near your house, you can also limit access to natural predators such as herons. If the koi are already large, such predators are unlikely to pose a threat to the koi. Young koi, on the other hand, become easy prey for herons and other pond predators. Since predators avoid human proximity, they can be kept at a distance if the pond is close to the house.

The koi also need shade. They cannot tolerate full sun all day. If you build the pond close to the house, the house can cast a shadow. Trees can provide shade, but you will need to remove leaves that fall into the pond to counteract the buildup of algae and mud.

3. The Suitable Pond Basin

Since the koi pond must be appropriately large, a prefabricated pond is hardly suitable. Prefabricated ponds are made of fiberglass-reinforced plastic and can be manufactured by specialized companies even in large dimensions. Such custom-made products in the appropriate size range are costly.

Therefore, you should create the koi pond yourself and dig a pit of the appropriate size.

The koi pond requires a solid substrate. If you have clay or loam soil in your garden, a solid foundation is guaranteed. You can line the pond with a pond liner, which should be at least one millimeter thick. When lining the pond pit, the liner should not wrinkle. This will prevent dirt and germs from settling in the folds. In the corners, you should cut the foil for a wrinkle-free laying out. Later, these places will be welded.

If there is no solid ground in your garden, the concrete pond basin must be poured to provide the necessary strength. Due to the size of the pond basin, you should have the concrete pouring done by a professional company. If the pond basin is lined with concrete, you must line it with foil.

4. The Appropriate Technique

Necessary for the koi pond and the life and health of the elegant pangolins is the proper technique. You must always pay attention to the correct water quality and check the water values regularly. You can do this with test strips and a color scale or even better with a droplet test. In summer, you should check the water values at least weekly.

To ensure consistently good water quality, you should equip your pond with a powerful filter. You should choose a filter that is too large rather than too small. This will help you avoid upgrading later, which can be time-consuming and expensive.

At the end of the filter, place a pond pump. It directs the water back into the pond.

Furthermore, it would help if you had a skimmer to keep the surface clean. Bottom drains are used to transport the polluted water into a mechanical and biological filter. To ensure that the bacteria in the biological filter are sufficiently supplied with oxygen, the biological filter should have good aeration.

5. Plants for the Koi Pond

Since the majestic giants have an unbridled appetite and will eat almost anything they can find, you should carefully select plants for the koi pond. Smaller and more delicate plants can quickly become victims of the glutton. Before planting your pond, make a planting plan. Hardy plants are best. Water lilies are well suited and have a high decorative value. They help clarify the water with their large leaves and provide good hiding places for the koi. They are also suitable for shading, as even koi are not immune to sunburn. This applies especially to animals with light skin.

It would be best if you also planted the bank. You should choose plants that provide shade.

6. The Right Care

Once you have created your koi pond, it comes down to proper care. You should

  • regularly check the water values and ensure a balance, for example, by changing the water.
  • regularly removing algae to prevent the water from tilting
  • removing leaves and other debris that have fallen into the pond to counteract the formation of algae
  • cleaning the pond twice a year, removing silt.


Koi inspire with their elegance, their colorfulness, and their trustfulness. However, you should carefully consider whether you are willing to take on the high maintenance and costs over many years. The koi pond must be large enough because the kings among the fish need a lot of space. You should choose the right location, which should be shady. You need the right technology in the form of a powerful filter and a pond pump. If you take all these tips to heart, the koi will feel at home with you.

Florian Egert

I am Florian Egert, the owner of I live with my wife and two children in Germany in a small village in the countryside.

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