How to Start a Koi Pond for Beginners

Most of us have had the experience of seeing an attractive koi pond in state parks, zoos, buildings, or other locations. Seeing these koi swim around happily in their ponds may have inspired you to want to have a koi pond of your own.

So, do you want to know how to start a koi pond? Start by thinking of the location, architecture/theme, size, depth, above or in-ground, shape, corners and the bottom. Then start digging your hole. Put some sand and salt in at the bottom.  Insert a pond liner. Add the water in. Add a filter. Aerate your pond. Purchase a skimmer. 

Start a Koi Pond By Digging Your Koi Pond OutKoi ponds are a beautiful and serene addition to add atmosphere to a public area. We are going to cover all the steps you need to go through to get your own do-it-yourself koi pond. I know that I boiled it down quite a bit so keep reading to get more details. We are fixing to go more in-depth. Are you ready?

Location Consideration For Your Koi Pond

The location of your pond is the first step. If you don’t get this right from the start then you could be facing an uphill battle for years. Some of the things to consider as far as location is concerned are:

  • Trees-building your pond under trees like pine will have the needles falling into your water no matter if you have a net or not. Trees with large leaves should be fine though.
  • Shade-In fact, those trees with the larger type of leaves would be perfect to have a koi pond under them. If your koi pond is in direct sunlight then the pond will quickly turn green with algae taking over.
  • Keep it privateDon’t have your pond in a publicly accessible area in order to prevent vandalism. Your backyard is your best bet since they are usually fenced in.
  • Keep it away from natural bodies of waterDo this to prevent run-off from accidentally flowing into your pond. 

Many people get their pond built when they didn’t choose the proper real estate to construct their pond on. Their pond is getting too much sun and they are constantly fighting the algae blooms. The ideal koi pond is an attractive piece of art that requires as little upkeep as possible. Battling algae all of the time will leave you feeling like your fighting a losing battle.

If you are one of those people that built your pond with the intention of giving your koi a tan then all is not lost. You can have a canopy put over your pond. Adding in plant life around your pond can be another way to control the sunlight.

Too much shade isn’t ideal either. Just as too much full-on sunshine isn’t good for your fish neither is too much dark shade. Ideally, you want some areas in sunlight and some in the shade. This will keep the water at an even temperature and keep your koi happy and healthy.

Decide On the Main Theme of Your Koi Pond

Every koi pond needs to have a general theme that it is built around. It doesn’t have to be Japanese-themed. A large majority of them is a Japanese theme as a way to pay homage to the country that started the koi hobby. You can have your own theme though. Like a favorite movie or favorite sports team.

Do you ever watch the show Tanked? I love the show. They take fish tanks and turn them into themed works of art for celebrities. These tanks’ themes are centered around the individual clients’ achievements or organizations they are passionate about. There’s no reason you can’t do the same thing with your koi pond except for your ability to actually do it of course. You can take care of that problem with this post hopefully

Size Matters

Digging Is How You Start A Koi Pond Construction

Decide how large you are willing to go on your pond. Make it big because all koi like wide-open spaces. Here are some things to consider on how small or large you want your koi pond to be:

  • You don’t want it so large as to make things like cleaning your pond, catching your fish(in case of illness), or viewing your fish impractical.
  • Reserve enough space for the filter

The ideal size for a koi pond many experts recommend is over 1,000 gallons. A rule of thumb is 10 gallons of water for every inch of fish. 

Depth of your Koi Pond

The depth of your koi pond is considered an important factor because a deeper pond will discourage predators. For this reason, a good pond depth would be six feet or more. If that’s not possible, then at least make it more than 3 feet deep.

The raccoons, Herons, cats, dogs, and other fish-eating critters won’t be able to catch fish in deeper water. Adding a net over your pond is also a good idea.

Obviously, adding more depth to your koi pond also increases the real estate that koi have to swim about happily in.

You can also put in electric fencing around your pond if it’s enclosed in. A raccoon might get passed an electrical fence but now it has pond netting it has to work through. And that waters deep so he/she can’t even reach in. Looks like that critter needs to find some other less secure pond.

Do You Want Your Koi Pond Above Ground or In the Ground?

The thing about koi is that their main beauty is seen from the top. That’s where you see all the brilliant colors and markings on them. So, if you can, try to make your pond an in-ground one. This will allow you to see your koi from an optimum angle.

If you are into a more natural look then you would also probably prefer an in-ground koi pond. Raised ponds look cool too and are easier to personalize if you go back to the theme section. In-ground pools look more natural though to you and I imagine the koi too.

What Shape Do You Want the Koi Pond to Be?

The pond’s shape can be whatever shape you can conceive of. The only important thing is to have constant water flow all throughout the pond. No stagnant areas where bacteria can gather and breed.

The Corners-The corners of your pond must be rounded off to prevent debris from collecting in them.

The Bottom- All about that base. Pond bottoms are not supposed to be flat. Instead, they need to be sloped inward at a 20-40 degree angle so the waste products can be collected into a distal settlement tank. 

Once you have your pond dug and the shape formed you need to add salt and sand to prevent unwanted plant growth and even out the base and then we move to the next step.

After Shaping Your Kio Pond-It is Time for the Liner

Pond Liners- These things serve as a barrier to keep your koi pond water from being absorbed into the surrounding soil. Koi pond water is very dirty and would be slightly toxic to the plant life surrounding the pond, so a pond liner is necessary.

 There are many different types of pond liners and they all have their pluses and minuses.

Concrete pond liners- If you are seeking the most permanent option and money isn’t an issue there is the concrete liner. These are pretty much permanent once these liners are installed. These won’t usually wear out in your lifetime.

The minuses of this type of liner are it tends to leach toxins into your water so you will want to check your water quality pretty often.

Another minus to these is their cost. They are the most expensive but you will never have to buy another one. So weigh your options.

Rigid Plastic Pond Liners- Now we come to the cheapest of the liners. These types of liners can also look natural and don’t take much damage from roots and sharp rocks.

The minus in here is they are the most difficult to install. It is hard to get the hole you have dug right so that it fits the liner without leaks and drainage occurring. 

These are more suitable for a warmer climate. 

Fiberglass Pond Liners- With these pond liners you get long life, ease in installment, and they don’t crack when under the ice.

The minus of these liners is they don’t look natural and you can’t hardly hide them.

Flexible Pond Liners- These are easy to install due to their flexibility. They are resistant to cracking under cold weather or heat. Flexible pond liners are non-toxic and inexpensive.

Before you start singing your praises to this type of pond liner the one drawback to them is their shorter life. They will last around 20 years, so you will have to relocate your fish at some point and replace the liner. 20 years is a long time though to enjoy your pond and your koi.

Your liner is in and now you are ready to fill the water in. This task actually is a tedious process but it is necessary so like the old Nike slogan- JUST DO IT. Please don’t copyright-strike me, Nike.

Filtration Systems

Your water needs to stay clean. How do you keep your water clean and serene? You do it by having a proper filtration system installed in. 

Without Filtration- Your pond will turn green and filled with sludge. Parasites will run rampantly unchecked and travel from fish to shining fish. The water will produce an obnoxious smell. You won’t be able to enjoy the pond you built and your fish will get sick or just die.

If you don’t get the point yet a proper filtration system is very important for your koi pond. Since it’s in the nature of koi carp to repeatedly stir up the sediment at the bottom of the pond this debris just floats around in the water taking the oxygen with it. The filter is what gets rid of this debris allowing water-soluble oxygen to circulate again for your fish to breathe.

There are two different types of pumps available to get the job done:

      • Submersible– Like the name implies these go under the water. People who have small ponds and fountains like these for being quiet and inconspicuous.
      • Recirculating– Recommended for bigger ponds due to their long-life and reliability.

The functions of a pond pump are two-fold. These functions are mechanical filtration and biological filtration.

Mechanical filtration is where the waste and by-products are physically trapped by the filter of the pump. Materials used in the filter are sand, pads, beads, and brushes.

Biological filtration converts the waste to something less invasive using a natural biological process.

Koi excrete ammonia which in large quantities are deadly. Filtering that stuff out is crucial. It produces anaerobic bacteria that can produce nitrites(another bad thing for koi.)

Some types of aerobic bacteria are ok for your koi when they convert nitrites to nitrates. Nitrates are not harmful to koi like the other type is. These good bacteria are called nitrifying bacteria.

You might have noticed me mention a bottom drain above. This drain will also trap the debris that would otherwise be floating around causing problems. It sucks out the dirty water via a pump that transfers said water to filter chambers. This drain should be at the deepest part of your pond. If you don’t add this drain you will be in for more cleaning being necessary to keep the water healthy for your koi carp.

Do you like waterfalls? Yeah? Me too. I got some great news because adding a waterfall is the most preferred method of aerating a pond. All that splashing at the bottom of the waterfall is what is adding in that extra bit of oxygen for your fish. You finally have a reason to get a waterfall of your very own. Exciting, huh?

There are two perpetrators that deplete the oxygen level in your koi pond:

      • Algae naturally take oxygen out to carry out photosynthesis. Controlling algae growth will be a task you have to do to maintain the serenity of your pond. 
      • Another perpetrator might be there are too many fish and not enough pond. There are too many koi competing for oxygen in a pond not equipped to supply it. Remember when I said size matters?

Aeration can be a way to distribute more of that much-needed oxygen throughout your pond. I like waterfalls because they are pleasing to the eye and sound soothing along with supplementing additional oxygen to my pet koi fish. 

If a waterfall isn’t possible then there are also devices like airstones and rings that require an air pump to operate. 

You can have both going too. Airstones and rings can be put at the bottom of the pond where oxygen isn’t as present as it is at the surface. 

The takeaway is your fish need the oxygen in the water to survive so purchasing a waterfall and airstones gives you more peace of mind that they are breathing comfortably.

Water Quality

Water has to be clean and safe for your koi. Fish need water like people need air, but both need oxygen. During daylight hours, algae and plants produce oxygen, but when the sun goes down they consume oxygen. That’s why you definitely need your air pumps to stay on at night.

Oxygen-The only way to determine the oxygen supply in the water is by using a digital oxygen meter. You should be fine with some kind of aeration device working your pond over. 

Nitrites– Nitrites are by-products of bacteria as ammonia is removed by the biological filter. They are toxic to koi. The way to remove them is through your pump. Make sure you have a pump big enough to move 30% of the ponds water volume at any given time.

Nitrates– Nitrates are not nearly as bad for koi as their cousin. They serve as a food source for algae and pond plants. You can control nitrate levels by allowing algae to grow on the inner walls of your pond. They will consume nitrates and level the levels out really well.

Ammonia– Ammonia is a byproduct of koi waste. Koi have to go just like we do. When they do it releases ammonia into the water and a large amount of it can be deadly to them. The solution to keeping it in check is by, once again, filtration.

pH Level– Raising and lowering the pH level in your pond is another skill you need to know as a pond owner. Vinegar is good for raising acidic levels if the waters not acidic enough. Baking Soda can be used to lower the acidic levels if the water’s too acidic. There are products on the market designed specifically for this though. The only way to check your waters pH level is by using a pH testing kit. 

Pond Skimmers

Many times debris gets blown into your pond. Leaves, flower petals, and organic debris produced by the pond itself. Eventually, all this junk will accumulate on the top of the pond and you need some way to remove it. That is the pond skimmer’s job.

Skimmers will trap the crap on the surface of the pond before it sinks and makes for a lighter load for your filters to filter through. 

Once you have the pond skimmer installed in you are all done with the heavy lifting. Now you are left with the job of maintaining your pond. All filters are in place-check. Aeration device-check. Bottom Drain installed-check. Happy koi-check.

You’re Finished! 

I’m glad you read to the end here. This is what you need to get your koi pond started. We covered all the bells and whistles needed to get a comfortable aquatic environment for your koi fish to swim about happily in. If you have any questions feel free to leave a comment or get on my contact page. Thanks.

How do you do predator control for a pond? There are many hungry predators that will kill your fish if you let them. So you need to prevent this from happening. You can:

  • Get a pond net to put over your pond.
  • A predator decoy will fool the other predators into thinking something else is already there
  • Electric fencing is good if your pond is already fenced in.
  • Scarecrow Sprinkler Systems look like scarecrows but also let out a stream of water if something gets too close to it scaring the villainous raccoon away. Would probably be pretty entertaining to watch too.

Are koi ponds high maintenance? Koi ponds can be hard to maintain if you don’t have proper filtration and the drain. Maintenance requirements include: 

  • Algae control– Get a net or something long to scoop the algae up. This is why it’s important not to make a pond too big. 
  • Check your koi over for open sores and herpes outbreaks. Quarantine them in a tank if you see these sores as they can spread it to your other fish.
  • Check the pH level of your water regularly
  • Check the oxygen level in the water in case it’s too depleted
  • Make sure all your devices are humming along smoothly
  • Feed your fish

How deep should a koi pond be? A koi pond should be at least 3 feet deep to account for the size a good koi is going to grow too. 6 feet is better to give them some fin-room. Digging 3 feet may not be permitted in your area though because of zoning laws. I’m lucky in that I live in the country so there isn’t much red tape to get through. Your area may be more strict.

How to build a koi pond with concrete? You can just dig the hole, fill the bottom with sand and salt to prevent too much growth, then insert a concrete liner. Be serious if you are going to use concrete because it is permanent. There’s no going back.

How much does it cost to build a koi pond? The price range of a koi pond is anywhere from  $1,171 to $4,889, with most buyers spending around $3,030. It varies so much depending on many factors like:

  • The ponds size
  • The type of liner you use
  • The filtration system you use
  • Predator protection devices and gizmos
  • Plants you buy
  • Is there stone around it?

Let’s Recap

I’m aware that this was a pretty long read, so let’s get down to brass tacks. You need a location with sun and shade both ideally. Make sure your koi pond is far enough away from other ponds to prevent runoff. This is probably the most critical factor for starting up your own koi pond so think on it well.

Think of your theme if you want a pond centered around one.  You can get together statues that represent your passion to place around the pond. I’m into rock music and there are cool guitar statues I can get. Check out Etsy for outdoor artwork that is pleasing to the peepers.

What shape do you want your pond?| Do the planning for what the shape is you want. An odd shape might make your pond look more natural like it just happened to form in your yard. A circular pattern might make it easier for upkeep though. Round off the corners in the pond when you’re done to prevent debris from accumulating.

Do the rest of the buildout. Put in the liner. Get your filter, pump, aerator, bottom drain, and anything else bought and installed. Do you have a net or fence for predator control? Put up that nice waterfall to give a relaxing trickling down of water into your pond that will oxygenate the water for your koi kids.

What do you think of my guide? You will learn more about building your pond out the more you work at it. It might actually become an addiction as it is really fun. Koi are really peaceful and in Japanese culture represent abundance and good fortune. As a sidenote: different species of koi represent different things, but that’s another post altogether. Enjoy working on your new backyard koi pond.

Do roots made digging hard? Not anymore! Introducing the Radius Garden 22011 Root Slayer Shovel, this shovel makes chopping roots up to get your pond dug a snap. It features: 

  • an inverted, v-shape tip with side teeth that saw and cut away roots
  • A blade made of powder-coated carbon steel
  • A latex-free handle

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You know you have to spend the next few weekends digging out your ponds shape. Why not make the task as easy as possible? You can check it out by clicking the image below.


12 thoughts on “How to Start a Koi Pond for Beginners”

  1. Wow, I have always wanted to have my own Koi Pond!  I never had a clue about how to build one until reading this article.

    I fell that Koi Ponds give such a beautiful and serene effect to any space.

    This is a great article and i will keep checking back to your website for more great ideas!

  2. Thanks for this post. For some time now, I have really been wanting to install a pond in our backyard to put fish in. I think the kids would really love it and I think it would look great. Thanks for the heads up on location. I use to think placing it under trees would be a problem, I understand better now about the best location to use.


    • Glad to have given you some insight into where to place a koi pond . Under trees is a great place as long as it isn’t the coniferous type. Pine tree needles will go right through the net so they aren’t a good type to put a pond under. Thanks for reading

  3. Wow! This is the best article guide anyone could ever wish for in building the koi pond. Even amateurs and professionals would still pick a couple of things to which they do not know before in this post. I am a nature enthusiast and I like getting very attached to nature and that is the reason I want to build a koi pond. I had actually thought the price of building it would be more costly than it actually is though. Also, the various factors that need to be put into considerations too are also a nice addition. Thanks for sharing this

    • Thank you. You’re too kind. Being a nature enthusiast is an excellent reason to give koi pond building a try. Let me know how it goes if and whenever you do. 

  4. It’s quite a detailed write up. I am still trying to familiarize myself with koi ponds, I have tried coming up with the common fish ponds but no so successfully, so I am going to have to read it all over again. 

    What I have learnt however id the need for providing oxygen at night when one decides to have plants on the pond, I guess this is what has been killing my set ups in the past. I’m going to try that fix and the many tips you have given out in my next one. 

    Thank you for this!

    • Glad to have helped. Oxygen is the most important element to your fish. I hope my tips lead you to getting an awesome fish pond set up.

  5. Very informative and rich content blog post.

    I am still on the planning stage of constructing my own house. Having a koi pond in my house’s yard will be a great addition. I am sure that it will bring harmony and serenity to the house’s surrounding.

    Wishing you all the best in your future endeavor.


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