How Much Does Koi Pond Maintenance Cost?

Typical Range:

$450 - $5,000

Find out how much your project will cost.

Cost data is based on research by HomeAdvisor.

Updated July 18, 2022

Written by HomeAdvisor.

Yearly pond maintenance costs an average of $2,000 for four servicing visits. People pay $450 on the low end and over $5,000 on the high end, but the price is heavily subjective and based on the size and complexity of the pond's environment. A single visit might cost as little as $250 to $450.

Ponds get dirty quickly because of their exposure to the elements. Unclean, standing water damages the health of anything growing within, like fish and aquatic plants. It also serves as a breeding ground for bacteria and algae that can make koi fish and other animals sick. 

Regular cleaning and maintenance should be part of any pond maintenance schedule, whether you decide to DIY or hire a pond cleaning pro.

Average Annual Pond Maintenance Costs

Low Cost Average Cost High Cost
$450 $2,000 $5,000

Pond Cleaning Cost Factors

The cost of pool maintenance heavily depends on the time of year, its location, size, if you need to replace the water, and whether the structure has a liner. A single cleaning costs between $450 to $1,000. However, larger bodies of water mean larger price tags. 


Many companies charge different amounts to clean a pond based on its size. In most cases, the company won't give an estimate and will charge by day since it's hard to tell to what degree the water needs sanitization and level of sediment removal. Other businesses charge based on how many gallons of water are present. Take a look at the typical prices to clean a pond based on gallon capacity.

Outdoor vs. Indoor

Indoor ponds are less expensive to clean because they are not as exposed to elements and debris like their outdoor counterparts. For example, an outdoor body of water might end up with bugs and leaves in it since it's near trees, and bugs often breed in the water. Since indoor ponds don't tend to have these problems, the monthly cleaning cost is usually as low as $30 to $40 a session.


Liners are a necessity when working with artificial bodies of water. The cost of a pond liner varies based on the material used, but they can prevent issues like land and chemical seepage from nearby terrain. However, liners complicate the cleaning process. Vinyl, plastic, and rubber liners tear under duress.

Cleaners need to be gentle when scooping out debris or trying to sanitize the water. Some types of materials also disintegrate when exposed to cleaning chemicals, which can leak other unhealthy byproducts into the water. If you don't know what type of pond liner you have, consult a pro to find out and make sure there are no interactions between the cleaners and the material. 

Never put a chemical in the water if you're unsure of its safety for use with your liner. 

Draining and Refilling

Sometimes, the water and buildup are too much to eliminate without draining. The process depends on the square footage of the pond and level of water removal. You'll also want to refill the pond afterward. 

It's expensive to fill a pond without using natural sources like a well or a nearby lake. Depending on the size of the pond, some homeowners like to reduce costs by using a combination of rain, well water, and a professional company.

Square FootagePrice to DrainPrice to Refill*
80$775 – $1,000$600 – $1,000
160$1,000 – $1,500$1,200 – $1,750
300$1,350 – $1,750$2,200 – $2,550
500$1,750 – $2,225$3,750 – $4,500

*The price to refill a pond varies by state based on water shortages. The above numbers account for states with lower costs, like Wisconsin, and those with higher costs, like California.

Waterfalls and Features 

Many people are willing to pay the price of installing waterfalls or fountains in their ponds because they are aesthetically pleasing and keep the water moving. However, the upkeep of these features can be costly. They require periodic maintenance and cleaning to stop clogs or contamination. Regular upkeep costs between $300 to $600 per year for professional cleaning and maintenance. 


Winterizing your pond involves preparing your fish, plants, pumps, filters, and the rest of the pond for the arrival of winter. Homeowners may DIY this job, but it’s always wise to hire professionals for help. Some of the steps involved include:

  1. Switching fish to a cold-weather food

  2. Trimming plants

  3. Changing the water and adding a dechlorinator or bacterial additive

  4. Pump removal

The whole winterizing process can be as little as $100 to $200, depending on your location and materials needed.

Pond Maintenance Cost by Type

The average price ranges between $450 and $5,000 per cleaning and maintenance session. Remember, though, that the overall expense of cleaning and regular maintenance will vary based on the type of pond. The main factors affecting cost are size, the type of cleaning needed, if there are fish in the pond, what kind of chemicals you are comfortable with, and what plants are present.


It costs about $500 to $1,500 to maintain a koi pond. However, the features you choose—as well as your location, property, inspection, maintenance, cleaning, and other elements—may push the price below or above this range. 

Other Fish

Property owners use fish-friendly chemicals that add $100 to $200 to the total cleaning cost but are safer for your gilled friends. Other fish still require clean water but don't need their environment changed as often as koi.

Small Garden

Pools with plants need flora-friendly chemicals that might add an extra $50 to $100 to regular maintenance expenses. Garden landscape ponds have few considerations that could increase the cost unless they have aquatic plants.

Natural Pool

Friendly chemicals add an extra $100 to $200 to the original price. Natural swimming pools should avoid using the same chemicals that pools with fish don't use. You can’t add some materials, like dechlorinators, which might make people ill.

Large Pond or Lake

Large pools and lakes cost more money for regular maintenance because of their size. The basic rule of thumb is to calculate the square footage and then multiply that number by $1.70 to $2.50 to find the average square foot cost for maintenance.

Detention and Retention

Detention and retention ponds need the same maintenance as other types. Their size affects cleaning costs. A detention pond holds excess water during periods of rain or snow. They are dry and don't hold water for more than 24 hours. A retention pond is like the back of a dam. It holds extra liquid should something happen to the main pond.

DIY Pond Cleaning vs. Hiring a Pro

Regular pond maintenance and cleaning can be a DIY job, but it tends to be easier, more convenient, and safer to hire a pond professional cleaner in your area. One of the main dangers of a DIY job is using the wrong amount or type of cleaners, which can kill fish or plants or wreck the environment of the water. Professionals also recommend products based on the body of water's size and can do more in-depth work like dredging. Pond dredging costs about $1.70 to $2.50 per square foot.

DIY homeowners purchase algaecides and muck removers for between $40 and $80, though larger ponds might need more product. Professionals charge more but bring their own chemicals and can save homeowners a day or two of work.


Are koi ponds low maintenance?

Well-made pools need regular maintenance, but it should be no more than a few minutes each week. However, it benefits from seasonal cleanings every three months as well. The amount of work that goes into the pond depends on its environment. Property owners who have ones with fish need to make sure the environment is habitable. Someone who wants to use theirs for swimming will want to ensure the water is clear and pleasant. It all depends on the style of pool and the homeowner's needs.

What chemicals are safe for fish and people?

Most chemicals used for maintenance are not safe for fish and people. Only use them after transferring the fish into a separate holding container. Some safe chemicals include tints, water clarifiers, and barley cleaners.

How much does it cost to fill a koi pond?

It costs $2,200 to $2,550 to fill a 300-square-foot koi pond. If you need to drain it first, expect to pay an additional $1,350 to $1,750.