Everything You Need to Know About Building and Maintaining a Koi Pond

A Koi pond is an essential element in the art of Koi-Keeping.  Koi fish are living jewels of elegance, charm, and beauty.  Traveling back to the Heian era, domesticating koi fish had already gained colossal traction among the nobles of Japan.  Records state that the nobles fed their koi with ‘Fu’, which was a royal delicacy at that time. ‘Fu’ is still an essential part of Japanese cuisine for both humans and their koi fish.  If you are a koi Kishi (a Japanese term for people who appreciate the koi fish and endorse their very existence), you must have surfed the web clean on koi How-tos. We are simplifying the process for you in one single quest for the ultimate koi fish pond in this article.  Before you commit to keeping koi, you must make some considerations to ensure that you have all that it takes to give your koi fish the best care possible.  Koi fish do not settle for anything less, and their royal Nippon blood craves commitment.  To begin your journey as a koi Kishi, there are few fundamental considerations that you must be making.

It all starts with a koi pond!

Why build a koi fishpond? Why not the good ol’ fish tanks?

There are several reasons why your koi will thrive better in a pond.  For starters, the natural habitat of a koi fish in lakes and streams that have a muddy bottom and a temperature of 70 degrees Fahrenheit or more.  The koi loves to forage constantly and for that, they need a bigger, more natural area where they can dance around all day.  Reproducing these conditions in a pond is far easier than any other type of fish accommodation.

Can you keep your koi fish indoors? Indoor space specification.

It is possible to keep your koi fish indoors, but for that, you will need a significantly large fish tank.  A well-fed Koi will grow quickly, meaning an indoor setting for your koi might be limiting for a lot of reasons.  If you are housing your koi in an aquarium, your koi can only reach the max size of 6 inches. When they grow 6 inches, they will need a larger area to flip and swim around.  Even if your koi fish has hatched recently, they reach 6 inches in two years, considering their longevity, you will invariably need an outdoor pond.

Sustaining a koi pond

The investment of time in caring for your koi fish changes varies with variables including seasons and geography.  You will have turbulent responsibilities and peaceful ones as well.  In this section, we will throw some more light on behavioral changes of your koi fish and the propionate type of care you need to provide.

The Summer Season [Total Care time- 2 hours and 20 minutes]

The caring routines for your koi pond during this season are a bit more strained.

Your weekly routine will include:

  • Cleaning the filter
  • Changing the water to ensure optimum water quality
  • Shading a considerable part of your pond. This prevents the growth of weed blankets.

The Winter Season [>30 minutes]

The winter season will give you plenty of room for relaxation, especially in the northern climate. 

Your weekly routine will include:

  • Keeping the pond covered to keep the water temperature close to 52-degree Fahrenheit.  A commercial pool cover will make the task easier for you.
  • Keeping a record of the koi pond temperature for each week.
  • Make sure the water chemistry of the pond remains suitable for your koi.
  • If you have a heating system for your pond, keep the thermostat at 62-degree Fahrenheit. 

The Spring Season [80 to 90 minutes]

For a spring pond, you simply must carry out some basic pond keeping chores. 

Your weekly routine will include:

  • Vacuuming out the muck from the pond
  • Partial water change
  • Cleaning and restarting the filter

Also read – Self Cleaning Fish Tanks That Actually Work

Koi pond equipment

Keeping your Koi fish indoors in a large fish aquarium certainly cuts the cost on your expenses when compared to a koi pond.  However, you must be aware of the fact the keeping your koi indoors is not ideal as a permanent home.  As the koi grow, an indoor setting becomes redundant, and you invariably must switch to a koi pond or give up on some of your beloved koi fish.  If you have made the choice to build a plan to keep your koi and you have the necessary dimensional requirement, it is time to tune into some gadget talk.  Here is a list of all the Koi fish Pond equipment you will require, and since our motto is to make it as convenient for you, we have integrated amazon links for each piece of equipment in the inventory.

FILTER SYSTEM – Cost: $500 to $1,200

If you have been keeping koi for quite a while now, you know, koi fish- well, they poop a lot! For those who are new, welcome to some blatant talk.   Koi fish pond needs a filter system with conjoined or separate mechanical and biological filtration units.  The biological filer will culture the nitrifying bacteria whereas the mechanical unit clears the pond of excess fecal matter and debris including dead leaves or fallen insects.  The word ‘filter system’ is as obscure and misleading, especially when for new koi-keeper.  You can choose a singular mechanical filter and ditch the biological or vice versa.  It is important to be aware of the difference between a mechanical filter and a biological filter to understand how each unit plays a crucial role in maintaining the integrity of your koi pond.

FISH NETTING – Cost: $45 to $75

A fishnet is another essential equipment for your Koi pond.  These nets are designed to cradle your koi without them getting snagged in the mesh.  Whenever you need to quarantine one of the koi fish or switch them in temporary accommodation for pond cleaning purposes, a koi fish net is your helping hand. 

POND HEATING SYSTEM – Cost: $500 to $1,200

Koi fish prefer an extremely specific water temperature, which could be between 30 – 90-degree Fahrenheit.  As the temperature fluctuates, the safety of your koi becomes compromised.  The Aeromonas Alley which is a temperature range between 40-50-degree Fahrenheit is a well-known red flag among Koi Kishis.  Within this temperature range, your koi are more susceptible to bacteria and other parasites present in the pond water.  A pond heating system is an effective equipment to overcome the Aeromonas Alley temperature range more swiftly.

There are three main types of heating systems that maintain an optimal temperature range in your pond:

·         Gas-Fired Boilers and heat exchangers

In a gas-filter broiler, the water contained within the heating system is circulated in a heat exchanger that keeps it warm.  The pond water is then pumped into a separate chamber.  This allows the heat from the water inside of the broiler to be transferred to the pond water before it is ejected.

·         Inline electric water Heater

In an inline electric water heater, the pond water passes through a heating chamber that has an electric heating element.  This passage of water through the heater raises its temperature as it is returned to the pond. 

·         Pond de-icers

Pond de-icers are the traditional variant of a koi fish pond heating system.  The deicer remains on the surface of the water, keeping the top layer from freezing.  Using a pond de-icer ensures that your water has a higher percentage of absorbed oxygen by keeping it ice-free and preventing the build-up of harmful gases. 

KOI POND MEDICATION – Cost: $50 to $350

Koi fish are known for their longevity, they have strong biological mechanisms to recuperate quickly from illnesses with assisted help.  Therefore, medicating your koi pond is a vital step to ensure that your koi always remains healthy.  Koi medications are grey zones for many koi owners, which is why it is important to educate yourself about the different health ailments of your koi fish and the best medications to keep your pond water, disease-free.

For more detailed guidance on Koi, medicines stay tuned and keep reading. 

PROTEIN SKIMMER – Cost: $50 to $150

Are you noticing gross scummy foam on top of your koi pond seems like a mystery even after installing high-end filtration units?  Well, such a condition typically surfaces when there is an excess of dissolved organic solids in your pond.  Your filtration system will fall short if not supplemented with a protein skimmer.  Dissolved organic solids are a result of koi metabolism as they go on depositing digestive materials into the pond.  The water protein levels go up dangerously high rapidly leading to foam formation.  Protein skimmers also known as foam fractionation units, remove the dissolved organic matter by absorbing them on the surface of fine bubbles.  As you run your protein skimmer routinely, it will eventually clear the pond of the foam and improve the overall quality of the water.

PUMPS – Cost: $300 to $450

The pumps are at the heart of efficient koi pond filtration units.  As the pump constantly runs without any breaks, you need to assess factors such as the pump’s reliability, running cost, and maintenance levels.   A koi pond pump of good quality and with appropriate specifications has better longevity and does not incur much utility costs.  Pump failures are rare unless it is a situation that cannot be covered by the pump’s control system including dry running, for several runs.  This might lead to your pump’s fatality even within an integrated thermal cut-out system.  When you are making a purchase stray clear of the koi pumps that are marketed as sump pumps.  Sump pumps are meant for short term operations and if you were to run them continuously, they typically die sooner. Make sure you follow the links we attach to pumps that are rated for continuous usage. 

UV STERILIZER – Cost: $225 to $400

A UV sterilizer is designed to stave off the algae that develop in the koi pond over time.  Ultra-Violet stops the formation of a single-celled organism from taking over the pond’s ecosystem.  These devices come with a safety mechanism that keeps your koi fish from getting injured.  If you have shopped around, you must have noticed that such units come with certain wattage ratings.  The power for the UV sterilizing system too comes with a wattage reading.  The larger your pond, the higher the wattage you will need.  This does not entail that you must overspend on such devices. Purchasing a UV sterilizer with optimal wattage in proportion to your koi pond will help save up money in the long run.

Funding – The koi maintenance cost

The main cash outlay for a koi fish pond includes several factors, your lifestyle as a koi Kishi can get expensive.  Certain variables including food, utility bills are predictable whereas others such as medication are harder to foresee.

Here are some of the common expenses for Koi keeping.

Food>$5 a month
Electricity [water pump, aerator, and UV sterilizer]$200 a month
Filtration System$20 a month
Water testing kits$50 to $12 a month

Your koi pond system will need replacement invariably as the filters and pumps burn out, but these are long term investments.  We advise you to stock up on all the essential medications before starting the koi pond project.  As with maintaining any ecosystem, it is expected that unpredictable expenses will arise should your koi encounter any medical problems.  Now we get to the real stuff, the more exciting stuff where you will be dealing with koi pond construction for a sustainable koi Kishi experience.

Koi Pond Planning

Koi ponds are surely one of the three certainties in life, well at least according to the koi Kishi principles.  A koi fish pond in your garden is a new dimension of koi-keeping. Keeping your koi fish indoor requires less commitment, and yet it is only a temporary solution.  After a time, your koi fish is bound to outgrow the fish tank.  A Koi pond, on the other hand, offers a long-term solution.  From now on, we will talk about the more interesting stuff that will help you decide whether a koi pond is the right decision for your koi fascinations.  If yes, we will discuss the complete process including pond location, size, materials, and much more to give you a more holistic idea on a koi pond.

Confirmations to avoid potential problems for your koi pond

Constructing a koi pond is more detailed than what you would expect.  Safety is important.  A koi fish pond is a fascinating view for adults and children alike.  Who can resist those metallic polished fishes that are super friendly?  Not fencing your koi pond is irresponsible as it jeopardizes the safety of small children.  To avoid such hazards, adding a fence around the koi pond works well for ensuring the safety of the spectators and your koi fish.

Securing the necessary permits for your koi pond

A koi Kishi is a real business, which means you need to prepare certain necessary permits for your koi fish pond construction.  As the rules apply, you will need to construct a sort of fence around the pond for safety purposes.  The permit costs vary largely, which makes it harder to estimate permit costs as each koi pond project is unique. 

How much space does a koi pond take?

To ascertain what size of koi pond you must build, you must contemplate on the actual size of your koi fish.  Another point that is more obscure but equally as important is the fact that koi fish have a big appetite and produce nitrogenous waste in no so small amounts.  If your pond is large, the ammonia will get diluted much faster which might reduce the burden on your pond’s filtration system.

The koi’s tossin’ and flickin’ space.

The art of keeping koi fishes is ancient, and so are the formulas to find the right number of koi you must add in one pond.  Our goal is to keep the crowd in your pond as minimal as possible for safety reasons.  Having said that instead of going deep into the formulations, let us take the middle road for simplicity.  Once you know the size of your koi fish, it is easy to figure out the size of the pond and the number of koi fishes you must keep – take out 1.5 inches of fish per square foot of the surface area.  To avoid crowding and allow for optimal growth of your koi, make sure you only keep a certain number of koi in the pond much below to the upper limits of the formula.

Here are some of the common koi fish sizes and the proportionate number of koi you can fit in a pond of specific size:

Size of Koi PondInches of koi @ 1.5 inch per sq. ft. of the pond’s surface areaNumber of koi in the pond if their size is close to 8 inchesFor koi in the pond if their size is close to 10 inches Number of koi in the pond if their size is close to 12 inches
6 × 9 ft.811087
8 × 12 ft114181412
10 × 14 ft210272117

Keep in mind that your fish will soon outgrow the accommodation if you have kept it small or add in too many koi in one pond.

A home for your koi – Pond Sizes

Keeping koi fish is a multifarious agenda in terms of dimensions.  It might take an entire year’s worth of space or just a corner of your yard.  The sizes also depend on your interest, finances, and the amount of time you can commit to building a koi fish pond and later maintaining it.

How much outdoor space do you need for a koi pond?

Two main factors come when you are contemplating over the pond size for your koi fish – the size of the pond and the area for other pond accessories including the filtration system.  One of the major concerns for many koi keepers is figuring out how deep the koi fish pond should be?  For the smallest size of koi pond (6 × 9 feet), the depth should be at least 4 feet which will contain approximately 1500 gallons of water. This size of the pond is enough to hold 10-12, 12 inches of koi fish.  Your pond must be large and deep enough to allow your koi fish to move in both directions without cramming.

Here are some more pointers that you need to keep in mind for your koi pond:

  • Make sure you leave at least 5 feet of access area along the length of your pond and a space for your filter along the shorter side.  This area will make it easier for you to feed and observe your koi fish.  This also invariably becomes the spot from where you can conduct basic chores such as netting out the sick fish and removing debris from the pond.
  • Keep 2 to 3 feet worth of area clear around your pond filter.  The space is necessary for backwashing, hose replacement, and winterizing the pond.
  • Assign some more extra space all around the general outline of your koi pond to prepare for pond leaks.
  • We do recommend keeping the necessary space for all the little components of the pond, but we also stress on not going extra with space.  Limiting the area of your koi pond is crucial for two major reasons:
  • While medicating the pond, the larger the pond is the more medicine you would need and higher the cost.
  • If you need to quarantine a koi fish among the others in the pond, a big pond will make it harder to net it.

How do I calculate how many gallons of water will fit into a specific Koi pond Size?

To begin with, you can do the following calculations to decide how much water will your koi pond holes:

  • Note down the dimensions of your pond
  • Multiply the length, width, and depth of the pond.
  • Multiply the end calculation with 7.48, which is the number of gallons in one cubic foot of water.

For instance, a pond with an area of 9feet × 6feet × 4feet is 216 cubic feet. When you multiply 216 with 7.48, you know that your koi pond can hold 1,615 gallons of water.

Securing the necessary permits for your koi pond

A koi Kishi is a real business, which means you need to prepare certain necessary permits for your koi pond construction.  As the rules apply, you will need to construct a sort of fence around the pond for safety purposes.  The permit costs vary largely, which makes it harder to estimate permit costs as each koi pond project is unique. 

Building A Koi Pond

To construct a koi pond, you will be essentially digging up a sizable hole in your yard.  You need materials that will serve as pond liners.   As the world of koi Kishi’s expanded, koi ponds have evolved from the original mud ponds in Japan.  To begin with, you can choose between a concrete pond or a liner pond.

Concrete pounds

Many koi keepers prefer concrete ponds for their apparent advantages even though it is a serious investment.  Small decorative insertions make a concrete koi pond look even more appealing added with the promised durability, concrete is the best choice as a preliminary koi pond liner.  Taking into consideration the rigidness of a concrete pond, you absolutely cannot scrimp on the raw materials. To do this, you must first begin with a solid budget.  Depending on the climate, if you are in a colder region, your pond needs to have a thickness of 6 inches and needs to be reinforced with rods or wire meshes.

Polyvinyl pond liners

Polyvinyl pond liners can vary thickness with the minimum for a koi pond being 20 millimeters for a single ply.  If you are going ahead with lining your pond with plastic liners, you need to make sure they are rated as fish grade plastic.  A 20 mm thick plastic liner can last up to 10 years, as the thickness increases, so do the longevity of the liner.  Another alternative to polyvinyl liners is butyl rubber liners that are not as easily accessible in the United States.  They are worth searching for, due to that they are not as easily affected by the constant sunlight pouring into your koi pond.  Koi hobbyists tend to choose plastic or rubber pond liners over concrete liners because plastic liners are more economical and require less assembly work.  Besides, the obvious advantages, PVC liners do have a disability.  As more time passes by the groundwork of your koi pond shift, so does the liner. The neat sides become obscure and although it is not as apparent to a spectator’s eye. This irregularity does drive Koi Kishi’s nuts.  For added durability, many koi owners add a double lining to their pond using both concrete which is then lined with a plastic liner. 

Good design makes all the difference in the long run

Like any other endeavor, building a koi pond with accuracy right from the beginning is much easier than covering up for mistakes later.  Make a catalog of the designs that will be the most suitable for your pond.  Lay all the potential shapes and angles using a garden hose to make a better assessment. Also consider how far you are ready to go with your commitment, if koi keeping seems like a lifelong choice for you, then you may as well build the largest pond within your limits.  If your koi-keeping is something less permanent and more fleeting a small and simple pond will suffice.

 The factored design aspects include:

  • Your koi pond must have at least one bottom drain for every 16sq ft as a part of the bottom area.  The floor of the pond should be tilted down in the direction of the drains. This slight tilt ensures that the detritus falling into the pond is channeled directly into the drains or towards the filtration system. 
  • Vertical walls with a depth of 4 feet are essential for your koi pond to make sure your fishes have enough room to escape predators as well as for more efficient temperature control.
  • Your pond should be clear of any gravel, sand flooring, or rocks.  A smooth and solid bottom ensures that there are no crannies for bacterial growth.
  • An external pump is a lifesaver when the one inside of the pond stops working. 

Digging a hole for your koi pond

This is the preliminary step for constructing a pond for your koi.  To do this, you can take assistance from the following:

  • Renting a backhoe, in this case, you will be doing the labor.  This needs considerable construction experience on your part. Going through with this option will cost at least $150 per day.
  • Hiring laborers to dig the koi pond hole. 

This method is more efficient as the work will be done in significantly less amount of time.  Hiring laborers will cost you around $15 per hour.

  • Dig the hole along with your friends.  If it is the weekend and you need some socializing, there is no better way to do that than to sweat it out for some productivity.

Digging a hole, that is easy!  Sure, when you consider the number of shovels of dirt you need to budget for a 9×6×4 pond hole.  It is a lot of things but simple.

Now that you have the necessary equipment and the help to plow the earth for your koi pond, here is the entire process in a few simple steps:

  • Use a garden hose to create a rough outline of your koi pond. Start with a basic oval or rectangular shape. 
  • Begin the process of excavating the pond hole.  You can build a ramp at one side of the pond to remove the dirt using a wheelbarrow or simply let your rental backhoe do the job.
  • After the excavation, you must lay out the concrete that will act as a footer underlying the walls of the pond.
  • Add wire braces along every two feet of the footer trench
  • You are the ready-made concrete into the same footer at the bottom of the pond.
  • The concrete will take at least 24 hours to cure. Good work! Maybe time for some barbeque with your friends. Go on you deserve it! 

Laying out the block walls

Even if you do not have prior experience of laying out a concrete block, which probably you do not. Do not worry, it is a laborious task but does not require much matriculation.  After you have allowed the concrete footer to cure for a day, here are the steps to carrying out a block layout:

  • To keep your blocks under proper alignment use stakes or strings as guides.  Begin by laying out the first layer of the block on either side of the koi pond, with the block opening facing the bottom.
  • Place the filter close within safety limits to the drains
  • You must use a level to even out the block rows while building the walls. 
  • Remember to lock the corners of the pond with alternating blocks on each side which is similar to the way block houses are built.
  • To enhance the strength of the walls, you can insert rebar into the walls. Then pump some concrete in-between the same walls to create one solid block.
  • Stop laying the block when you have only 3 inches of the upper edge left counting from ground level. 

After you block laying, comes the part where you place the liners and the plumbing.  This completes the cementing process of the koi fish pond.

Drain alignment

Once the cementing is done and dry, your pond is ready to install the drainage system, but before you start with aligning the drains, you need to install the plumbing outside of the koi pond for the filter.

Here are the necessary steps for plumbing and installing a drainage system:

  • Begin by excavating a trench on the pond’s edge for the installation point.
  • Run 3 inches of 4 inches of PVC pipes along the edge of the trench.
  • Now, you need to backfill the walls of the lines trench with sand or gravel.  Tamp it into place after each addition.
  • All that is left now is to place the filter drains on the pond floor, on equal distance from one another.
  • Once the drainpipes are in place, add dirt to the bottom of the pond to have a slanted floor.  The direction of the slant should be towards the drains.

Now you have a basic shell for your koi pond.  It is time to install the filtration system. You can purchase the appropriate filter that suits the design of your pond the best.  We have certainly made the process easier for you in the equipment section above by mentioning the types of koi pond filters and where you can find them with ease. 

Adding lights to koi ponds

Many koi hobbyists wonder if it is safe to add lights to their koi fish pond.  Well, traditional koi ponds do not have underwater lighting, but that does not mean yours cannot.  Although we do advise that you keep the artificial lighting to a minimum, your koi might find a lot of bling-bling as intrusive.  If you love the view of your koi swimming at night, a few lights are the perfect décor for the pond. 

Purchasing a preformed pond

The plastic pond liners in an average pet shop might not suffice for a more intricate koi pond.  Several outlets deal in custom made outdoor pond and fish items that can provide you with the ready- or custom-made pond liners.  Their outlets have a variety of pond liners which are sizeable with shelved divisions along the edges.  You can also buy a preformed fiberglass mini-pool that can be delivered to your home.  Their pools are often colored with a turquoise dye, which is neither too dark nor too light.

Beautify your koi pond

Your koi pond is the focal point of your garden or yard, and after all the hard work, it better be the center of attention. Right?  Right!  If your koi fish pond looks a bit unadorned and you also want a few elements for fishes to play with without affecting the delicate ecosystem.  We have the perfect solution for you- Landscaping.  Living plants are the perfect addition to your outdoor koi pond.  Now that you have tried at koi keeping, how about some water gardening, eh?  I am quite sure you are already thinking of a lavish display of lilies or lotus or all those other aquatic plants you have seen in Japanese koi paintings.   Sure, but that’s still life, everything works there. In real life, koi fishes are little funny pigs that will eat your Vallisneria or lotus or Anacharis. You name it!  Don’t worry, you can still create a perfectly balanced environment where you can add plants to the pond without them turning up on your koi’s lunch menu.

Here are some koi fish pond fashioning 101s for you:

  • A good way to help your koi and the plants to coexist is by creating separate areas in the form of sub ponds or bogs that are around a foot deep.  There are two ways through which you create these separate spaces – a brick wall or a low ridge of soil.
  • These shallow areas can be placed anywhere in your pond.  Most of the koi pond owners prefer to place them near the filtration system.  As the water flows along the length of the bog, the plant will consume the nitrates present in the pond water.  This will reduce the dissolved organic waste in your pond and allow your plants to flourish.  Seems like a win-win situation to us!

Some of the common bog plants used for koi ponds include Turtlehead, Joe Pye weed, swamp milkweed, and chameleon plant.  You can use plastic plants at the edge of the koi pond. This serves the purpose of providing shade for your koi from harsh sunlight and is a hassle-free option when compared to natural plants.  There are two variants for koi fish pond landscaping – the Japanese style, which is plain and simple or a more natural jungle-like environment.  Both the jobs give new life to your koi pond and create opportunities for your koi to play around.  Entertainment matters for all. Eh!

Maintaining your Koi Pond

After investing your time and money in building and designing your koi pond, comes the task of keeping the conditions in the pond at an optimal level.  This is a never-ending job for as long as you carry out your koi keeping hobby.  Laborious but pays off in the long run.  If you follow the guidelines, we can help you by simplifying the steps that go into koi pond maintenance.

Equipment maintenance

Much like another machine, electrical and mechanical equipment are subject to wear and tear. You already know that. Ok!  A Little heads ups with help you prepare better in advance.

EquipmentLongevity or replacement duration
Filters2 years
Water pump3 years
Air pump5 years
Pond liner5 years [usually replaced along with the air pump]
ConcreteNever [that is the charm of concrete koi ponds]

Water chemistry

Koi fish are hardy, but a prolonged imbalance in water chemistry can reduce their lifespan significantly.  This is conducting routine checks, and testing out the chemistry of the pond water becomes essential.  Here are the following elements in the water that you need to track and keep under control:


The optimal ammonia level in your koi pond water should be at the 0 marks.  The ammonia levels rise especially after you have fed your koi.  You can reduce the ammonia levels by diluting the water which can be done as a partial water change.  However, if your ponds ammonia levels remain high even after the dilution, you need to look at the following reasons:

  • New pond syndrome, which is a normal phenomenon in a newly constructed pond. It is characterized by inconsistencies in water chemistry readings.  This problem solves itself within six weeks naturally.  During this period, you need to monitor for any signs of distress in your koi fish and conduct partial water changes to make sure the condition does not worsen.
  • There might be a deficiency in your pumps, or you might have added way too many koi fish in one pond. 

To check if your pump is doing its job, you can attach a flow meter, to calculate the output in every 15 minutes.  By multiplying the reading, you get with 8 you can determine if the pump is pushing out enough water for optimal circulation.


The perfect pH range for your koi pond is 6.8 to 7.2. If the pH of your water is going towards a lower range, you need to start worrying about your koi as well as your biofilter.  The good bacteria in your koi pond will die when the pH goes below 6.  As the bacteria die off, so does the process of ammonia conversion to less toxic nitrates and nitrites.  As the ammonia level shoots up, it could cause distress to your koi and can also prove to be fatal.  If the pH inconsistencies are minimal, your pond is virtually safe.  The koi are adaptive and can tolerate slight pH changes.  You need to take these readings at heart if they are not extreme. 


Much like ammonia nitrites are direct by-products of digestion.  You want to keep the nitrate level as low as possible.  Your filtration system is enough to keep these levels.  You also need to keep making partial water changes, dilution is the best method to keep all levels balanced especially for a new pond.

Dissolved oxygen

The amount of oxygen in your koi pond is another important element to ensure a steady, dynamic ecosystem in your koi.  A lot of components use up this dissolved oxygen in the pond water including your koi fish, bacteria, and the decomposing organic substances.  With new ponds placing, the oxygenation device is a great way to keep the oxygen level up at all times.  

Changing the water of your koi pond

Partial water changes crucial for koi-keeping.  Changing the water in your koi pond is an inexpensive way to maintain the integrity of the ecosystem.  By doing that, you are diluting all the bad elements that are a result of the waste produced by your koi fish.   Partial water changes also help in keeping the water temperature within a moderate scale.  

Maintaining a steady temperature in your koi pond

The ideal temperature range for your koi pond is around 70 to 80 degrees Fahrenheit.  Sudden and unprecedented temperature drops distress your koi fish.  Adding salt to your pond helps your koi deal better with the temperature changes.  The ratio of salt to salt for your koi fish pond is 3 pounds for every 100 gallons.  Since salt dissolves quickly in water, avoid adding it all in a single heap.  Rather make a salt solution and add It between short intervals. 

Koi pond is a dynamic ecosystem for your koi fish.  By building and maintaining a pond, you are not only giving the best home to your koi but also reaping the rewards afterwards.  Sitting in your yard watching your koi glide through the water with their beady eyes and metal glazed skin can be is a life-long gratification. Once you have a permanent home for your koi, we have another article on a detailed counseling of how to keep your koi fish healthy and what to do should they succumb to an illness. STAY TUNED!

Also read – Best 30 Gallon Saltwater Fish Tanks

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