Most people are familiar with the beautiful and brightly-colored Japanese koi. A type of common carp, koi have been bred for over 1000 years, resulting in many color combinations.
You may have seen photos of koi ponds or even visited a one yourself.
There’s nothing like standing on the edge of the water and seeing the fish rise to the surface.
Are you interested in having a koi pond in your backyard? You can. Here’s how.
In this article
Start with realistic expectations
Many of the most exotic and beautiful koi ponds are quite large and decorated with rocks, trees, and a waterfall.
It’s not unusual for koi enthusiasts to bring in a bulldozer to excavate the pond and a crane to place the rocks on the waterfall.
You’ll need a professional installation crew if this is your idea of a koi pond.
But for most of us, we’re happy with a more-simple DIY backyard pond.
Koi pond vs water garden
Water gardens are designed for keeping a variety of aquatic plants and some goldfish.
However, koi and pond plants don’t mix. Koi are very curious and powerful “diggers”.
They’ll knock over potted plants, disturb the soil and eat the plants. Your pond will turn into a muddy mess.
As koi grow, they need room to freely swim throughout the pond. A koi pond is designed solely for koi.
Important koi pond features
Here are the basic characteristics of a koi pond:
- At least 4-feet (1.2 m) deep to resist fluctuations in water temperature and over-wintering.
- 1500-2000 gallons (5678-7570 l) is a good size for a DIY koi pond.
- Koi will reach a length of about 32 inches (81 cm) long. They need room to swim, so make the pond as large as possible (at least 1000 gallons/3785 l).
- Unlike water gardens, koi ponds are built to maximize depth by eliminating sloping sides.
- Koi need excellent water quality to stay healthy.
Koi basics
Young koi are often offered for sale as small as three inches. Given proper care, they’ll grow to an average length of three feet.
Koi have the typical elongated body like their carp ancestors. Their mouth faces downward toward making it easy to forage along the bottom of the muddy pond.
Koi have two pairs of barbels on each side of their mouth. Barbel is Latin for “little beard.”
Barbels are sensory organs used for detecting food by taste. Koi use their barbels to sense food buried in muddy sediments.
These fish love to eat plants. They have rather large, powerful mouths that can ingest small aquatic pond plants.
Koi will munch on lily leaves and the roots of floating plants. Their inquisitive nature leads them to dig around potted plants, spilling the soil and uprooting the plants.
Koi require exceptional water quality to remain colorful and healthy.
They are not hard to keep but the pond’s water must be properly filtered, and fish fed correctly to maintain good water quality.
How many koi can I have?
Assuming the pond is between 1500 and 2000 gallons (5678-7570 l), and you are starting off with koi that are less than 10 inches long (25 cm), you can keep six to eight fish.
You may be tempted to add more but remember, your fish will grow to at least 12 inches (30 cm) in length.
As they grow, they need more oxygen, create more waste, and require more room to swim.
Packing the pond with koi only leads to poor water quality and disease problems.
The idea is to raise your young fish over the years so they can live a long, happy, and colorful life.
Tips for selecting your pond’s location
Your koi pond can be in full or partial shade. Sunlight helps you see your colorful koi in the pond. It also makes it easier to select plants for landscaping around the outside of pond.
If you try to dig the pond close to a tree, you may have difficulty cutting through tree roots.
Falling leaves can also accumulate in the pond, clogging the filter and causing a decline in water quality.
It’s best to install the pond away from trees. Here are a few tips for selecting your pond’s location:
- Avoid overhanging trees.
- Stay away from low or wet areas as they can divert surface water into the pond.
- Place the pond where it will be easy to view.
- You’ll need electricity nearby for the filtration system.
- It helps to have a water source close by for filling and topping off the pond.
Why use a koi pond kit?
Once you’ve decided to build a koi pond, you’ll need to select everything from the pond liner to the filter system.
There are many choices when it comes to assembling all the materials needed for a pond.
Purchasing a koi pond kit takes the guesswork out of selecting the components. All the design work has been completed, making it simple to get everything you need in a single purchase.
Going with a pond kit ensures all the components are matched and will work together.
You’ll also have the support of the manufacturer in case you have questions or need a spare part.
Key Features of a Koi Pond Kit
When shopping for a koi pond kit it’s helpful to know what features to look for.
Here’s a list of standard components used in high-quality koi pond kits:
- EPDM rubber pond liner: Most kits come with a rubber or plastic liner that is both flexible and puncture-resistant. 45-mil is a common thickness. Liners take the shape of the hole, making it easy to get the shape you want.
- Underlayment: A cushiony, protective material that is placed into the hole before installing the liner. It protects the liner from roots, stones, and other sharp objects.
- Submersible water pump: The pump brings water into the filter and out through a fountain or waterfall.
- Filtration system: Koi ponds require a filter to keep the water clean and free of suspended debris.
- Skimmer system: A surface skimmer pulls water from the pond’s surface. Skimmers keep debris off the surface, preventing it from collecting on the bottom of the pond.
Optional Pond Equipment
Some koi pond kits are available with advanced equipment or options like underwater lighting.
- UV Clarifier: A UV clarifier uses a special UV-C bulb inside a water-proof housing. As water passes by the UV light, it kills algae, keeping your pond water crystal clear.
- Water conditioner: Chlorinated tap water is harmful to koi. Use a water conditioner that neutralizes chlorine disinfectants, making tap water safe.
- Bottom drain: Bottom drains pull water into the pump and filter system through a hard-piped plastic drain at the lowest point in the pond. It requires cutting the liner and running PVC pipe. Bottom drains are used most often on larger koi ponds.
Best Rated Pond Kit Reviews
We took a look at four koi pond kits for our review. Three of the kits are suitable for keeping a few small to medium koi.
We also included a larger pond kit in case you want to go big and keep even more beautiful koi.
The Savio 3000 15 x 20 koi pond kit states you can build an 11 ft. x 16 ft. pond with a depth of 1.5 feet.
This is too shallow for koi. Your pond should be at least three feet deep. By digging deeper, you’ll reduce the pond’s width and length somewhat.
Another option is the 20’ x 25’ option. It will allow you to create the proper depth and have a larger surface area.
The kits come complete with a matched 3,000 GPH submersible pump, 25 feet of hose, and a skimmer-filter system. This includes a waterfall system that returns filtered water back to the pond.
The pond liner is made of 45-mil EPDM LifeGuard Pond Liner has a limited lifetime warranty when installed with included underlayment.
The Savio kits include a UV clarifier to keep the water crystal clear.
The kit also includes an air pump to provide extra oxygen for the koi, a water conditioner, bronze underwater light, and black foam adhesive for securing rocks around the pond and waterfall.
The Savio Select 2000 pond kit has much of the same features as the Savio 3000 kit. It does not come with a UV clarifier.
The manufacturer says the kit will create a pond measuring 15’ x 20’ with a depth of 1.5’. This is too shallow for keeping koi.
You’ll have to dig the hole deeper to provide your koi with the proper depth. This will reduce the length and width of the pond.
The Select 2000 kit includes a surface skimmer, submersible return pump, and waterfall return kit. 25 feet of flexible hose is included.
Like the 3000, you’ll receive a submersible bronze light, water conditioner, and black foam adhesive.
The Simply Ponds 2100 kit comes with a 15’ x 20’ 45-mil EPDM liner with a limited lifetime warranty.
Like other pond kits, you’ll have to dig the pond deeper for koi.
The kit includes 300 square feet of UnderGuard underlayment fabric to protect the liner from rocks and punctures.
The Manta 2,100 GPH submersible water pump has a two-year warranty.
The surface skimmer has faux rock lid, mesh basket that captures leaves, and filter mat that removes fine debris.
The waterfall also has filter mat. Waterfall Foam is included to seal gaps between rocks, preventing accidental water loss.
The Simply Ponds 2100 kit comes with a submersible LED pond light and a bottle of beneficial bacteria to start the pond’s bio filter.
This pond kit comes with a large 45-mil 21’ x 26’ liner, making it suitable for a small starter pond for very small koi.
One of the largest pond kits available. A big pond requires a big filter, and this kit doesn’t skimp.
The Signature Series 1000 Pond Skimmer System and matching Signature Series 6000 BioFalls Biological Filter System are designed for the higher flow rates needed to keep the pond healthy.
The AquaSurge 4000-8000 Adjustable Flow Pump has the power to move a lot of water through the filter system.
The water pump’s flow rate can be controlled with an app on your smart device. You’ll be able to shut the pump off while feeding your koi floating pellets.
The Aquascape pond kit also comes with several submersible LED lights to illuminate the pond.
An automatic dosing system can be used to treat the pond with beneficial bacteria and other water treatments.
The installation kit contains silicone, pond and waterfall foam sealant, and PVC cement in case you’re using pipe.
The Welcome Kit includes a fish food sample and water conditioner.
Recommendations
The Savio pond kits are similar in size and features.
The main difference is that the Savio 3000 kit includes an integrated UV clarifier. While you can always add one, it is easier to go with a kit that includes a matched UV unit.
Both kits have a limited lifetime warranty of the pond liner. Either kit works well for a backyard koi pond.
Knowing that koi like to glide around the pond and grow to over 12 inches, the Aquascape large pond kit may be right for you.
You’ll be able to have a larger surface pond area and the depth required to keep larger koi. Plus, the kit includes a properly-sized filter and pump.
If you have questions or comments, please leave them below.