An authentic Japanese koi pond goes far beyond the classic garden pond. To get started on the ambitious construction project, you should collect important basic information if you build the pond system yourself. This guide gives an overall overview of the minimum requirements for the perfect koi pond in the hobby garden. Be inspired by ideas for creative design.
How do you build a koi pond in your hobby garden yourself?
A koi pond in the hobby garden requires at least 10,000-20,000 liters of water, 1.50 m deep, a filter system, skimmers and plants. You can design the pond yourself with pond liner or pond tray and use useful accessories such as oxygen pump, winter cover and frost monitor. Also consider location-related factors and the needs of the fish.
- Basic requirements for a koi pond are: 10,000-20,000 liters of water, 1.50 m depth, filter system, skimmer and plants. Useful accessories include: oxygen pump, winter cover, frost monitor.
- Building a koi pond in the hobby garden can be done on your own using a pond tub or pond liner. Sophisticated expert options include: Building a koi pond out of concrete or building a wall.
- S alting koi ponds is not an effective way to combat algae.
Building a koi pond – what does it involve?
A koi pond is a demanding garden project
There are worlds between a conventional garden pond and an original koi pond. In the koi pond, everything revolves around the well-being of the magnificent brocade carp. The following table provides an insight into the mandatory framework for building koi ponds and lists important accessories for clear water and happy fish. Be inspired by creative ideas for a picturesque water world that invites you to dream and linger.
| Planning/Construction | What to pay attention to? | Accessories | Tips | Creating/Planting | Ideas |
|---|---|---|---|---|---|
| Minimum size | 10,000-20,000 liters | Filter system | Pond filter with floor drain | Bedge planting | Bamboo cattails |
| Minimum depth | 150 cm (at the lowest point) | Skimmer | floating extractor | Aquatic plants | Water lilies, swimming fern |
| Amount of water per koi | 1,000-2,000 liters | UV lamp | decorative bacteria killer | Underwater plants | Mermaid Weed, Waterweed |
| Location | partially shaded, close to the house | Ventilation | Air lift to ozone system | Decorative algae killer | Plant Island |
| Material | Pond liner, pond tub | Pond heater | Frost monitor to heat exchanger | Oxygen plus | Waterfall |
In the following video, an experienced Koi expert has his say with practical tips about the ideal Koi pond in the hobby garden.
10 TIPS - Neueinstieg Koiteich
Build your own koi pond – tips for newbies
The information in the table above suggests it. When planning and building a koi pond, dimensions that a small hobby garden cannot offer must be taken into account. Mandatory accessories for clear water and he althy fish require a well-padded financial budget. Please read the following in-depth information if you are building a pond for koi carp yourself:
Planning and construction
The simplest version for building a koi pond yourself is the pond tray. Scope, koi-friendly depth and capacity are specified. If you want more flexibility, use pond liner. In both cases, a rented mini excavator digs the pit, including the trenches for inlet and outlet pipes. Savings hunters use the excavated soil to create a decorative planting mound instead of digging deep into their pockets for disposal. The whole family gets involved in laying the pond liner and root protection fleece.
Hobby gardeners with well-filled wallets build a koi pond out of concrete that will last forever. With a little craftsmanship, you can build the pond system yourself in order to cover the higher costs that would be incurred compared to building it with pond liner. Whether brick or concrete - in both cases you need knowledgeable experts who can provide you with advice and support during planning and construction. It is a risky undertaking to simply download building instructions from the Internet and use them without checking them.
Building a pond with a pond liner is cheaper than concrete, but less durable
Basic accessories
A filter system with a bottom drain is mandatory for every koi pond. Builders are spoiled for choice from numerous models with different functions. Biofilters, brush filters, drum filters, cartridge filters, plant filters, multi-chamber filters, endless belt filters, barrel filters and many more are offered. Most pond filters are pump-operated and contain special filter material, such as zeolite, which also absorbs excessive nitrite. To ensure that green water is a foreign word for your koi pond, we recommend purchasing additional accessories:
- Floor drain: for every 10,000 liters of pond water, a 110 mm floor drain at the bottom of the pond
- Skimmer: floating surface cleaner sucks away waste
- UV lamp: Fight bacteria, algae and filamentous algae with light, modern, innovative and without chemicals
- Ventilation: Oxygen supply simply with air lift, classic with flow pump, modern with ozone system
Winter puts koi carp to a tough test. Because temperatures below 5° Celsius mean a death sentence for the valuable fish, you should cover the koi pond in winter and make it winter-proof in this way. A pond cover buffers the high heat loss across the water surface. In addition to the winter cover, install a pond heater. Even an inexpensive frost monitor prevents a fatal drop in temperature. High-quality solutions regulate the water temperature to a koi-friendly 15° to 20° Celsius using a heat exchanger.
Tip
Robust breeds measuring 20 cm or more are recommended as the first inhabitants of the koi pond. Ideally, choose Koi carp between the ages of 3 and 4 years, who, thanks to their life experience, will be able to forgive one or two beginner mistakes and deal with them without harm.
Creating a koi pond – ideas for creative design
Embedding the koi pond in its natural environment while always keeping the well-being of the fish in mind is one of the special challenges. When it comes to green design, hobby gardeners have a clear advantage, thanks to their experience in dealing with the plant world. Against this background, we are able to build a bridge to creative planting that simultaneously purifies the water and supplies oxygen. Let the following ideas inspire you:
- Bedge planting: Bearded iris (iris), loosestrife (Lythrum salicaria), stream bung (Veronica beccabunga)
- Aquatic plants: Water lily/water lily (Nymphea marliacea), duckweed (Lemna trisulca), shell flower (Pistia stratiotes),
- Underwater plants: Comb pondweed (Potamogeton pectinatus), water feather (Hottonia palustris), hornwort (Ceratophyllum demersum)
A floating plant island harmonizes wonderfully with water lilies and brings variety to the appearance. Easy-care pond plants such as dwarf rush (Juncus ensifolius), marsh marigold (C altha palustris) or water mint (Mentha aquatica), which are useful as natural algae killers, are perfect for planting.
Visual highlight and natural oxygen supplier is a waterfall that you can build yourself using simple means.
Excursus
Koi – demanding, trusting, long-lived
Koi are very demanding fish
The bar is set high when you build the right pond for demanding koi carp yourself. The reward for months of planning, strenuous effort and high costs is a romantic water world as an oasis of well-being for the whole family. When the noble brocade carp swim around weightlessly, crystal clear water gently ripples and flowering pond plants sway gently in the wind, the worries of everyday life become a distant memory. The majestic fish trustingly look for you on the bank and make your heart beat faster. The relaxing idyll accompanies your life from now on, because a koi can live up to 60 years.
S alt koi pond? – Tips for the best water quality
The ultimate discipline in koi pond care is top water quality. Green water and harmful pH values often cause headaches for newcomers. Home remedies are circulating on the Internet as solutions to problems, which at best have no effect and at worst cause considerable damage. S alt and milk have failed to combat algae. The following tips get to the heart of what needs to be done to improve the water parameters:
Green water – what to do?
The cause of green water in the koi pond is an algae bloom. The explosive proliferation of green algae, floating algae and filamentous algae is triggered by rotting plants, rotten fish food, flooding of soil or fertilizer and fish carcasses. How to act correctly:
- Remove contaminants from the water, such as leaves, plant parts, carcasses, leftover food
- Sprinkle organic products from specialist retailers into the water, such as KOIPON Pond Clear (€31.00 at Amazon)
- Install UV lamp so that algae flocculates and is easy to remove
Preventative measures include using a floating plant island and numerous aquatic plants as biofilters in the koi pond.
PH value is not correct – what to do?
Regular water testing is a mandatory part of koi pond care. In particular, the pH value must be checked promptly because a value that is too high or too low is fatal for koi carp. According to the table, the ideal pH value for the koi pond is 6.5 to 8.5. This is what to do if the pH value is not correct:
- PH value greater than 8.5: Fill a cotton bag with unfertilized peat and hang it in the water, place an oak branch in the water, buy pH-minus from a specialist store and put it in according to the instructions Give pond water
- PH value less than 6.5: Change the water with tap water, put limestone in the water
There is a close connection between the pH value, the carbonate hardness and the Co2 content (carbon dioxide). Therefore, please subject all water values to a continuous check in order to intervene in a timely manner in the event of fluctuations.
Frequently asked questions
How big does a koi pond have to be for 5 fish?
A koi pond must be sufficiently large
Plan a space requirement of around 30 square meters for a koi pond with 5 fish. A koi carp needs 2,000 liters of water to develop he althily and vitally. In purely mathematical terms, this means you have a pond volume of at least 10,000 liters (10 m³).
Which filter is suitable for a koi pond?
Full-length theme among Koi lovers is the best filter system for the pond. The range of products on the market is dizzying and extends from natural filter trenches to simple fleece filters to high-quality, technical filter systems, such as the fully automatic drum filter with an integrated biochamber for several thousand euros. As a rule of thumb, the best filter should circulate the pond water at least once an hour. All further decisions depend on the local conditions and of course your wallet.
How much s alt goes into a koi pond?
You should only s alt a koi pond if all the koi carp in it are suffering from ascites. In this case, a dosage of 2 to 5 kg of iodized s alt per m³ of pond volume is beneficial. If individual specimens suffer from the disease, we recommend a s alt bath in a separate treatment tub. Contrary to popular opinion, you will not achieve any effect in combating algae if you add s alt to the koi pond.
In my koi pond, foam floats on the surface of the water. What to do?
Foam formation on the water is a serious warning signal for the biological balance in the pond. The foaming water surface is caused by excrement and leftover food, which produce an excess of protein. You can solve the problem effectively and permanently with a protein skimmer, a special pond technology device. An immediate water change also ensures clear conditions in the foaming koi pond.
Tip
Pampered koi love to eat several times a day. An automatic feeder serves meals to the fish when you are at work or on vacation. Simple, battery-operated devices can be purchased for less than 80 euros. Luxury models work energy-consciously with solar power, are a decorative feast for the eyes and cost up to 1,000 euros.
