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The Koenders Difference

Koenders Windmills invented the aeration windmill in 1988. During the last 27 years we have supplied our customers with over 75,000 windmills and electric aerators. Most of the Generation 1 and 2 windmills sold during the first few years are still in service. That's 25 to 27 years of standing up to Mother Nature through both high and low temperature extremes, snow storms, dust storms...every imaginable form of severe weather.

Our history and experience is now producing Gen 6 models of Koenders Windmills so today’s customers can be assured they are purchasing the most durable and efficient windmill and electric aeration systems available on the market.

How about our customers who require maintenance parts or replacement parts?

BEWARE of OFF BRAND or KNOCK OFF Koenders parts and products and companies that are promoting them. In the past 12 months we have had numerous complaints from customers about product parts that have been purchased from companies whom they thought were authorized to sell Koenders products and whom they were led to believe were buying Original Koenders products and parts. When they call Koenders Support they find out these parts did not fit or they broke prematurely or they voided their product warranty.

Most of these online retailers are NOT AUTHORIZED KOENDERS DEALERS. They will tell you these parts are as good as the Original Koenders parts or even that they are genuine Koenders replacement parts when indeed they are not!

People who have purchased these parts have reported to our Koenders representatives that these parts either did not fit correctly...or that the part failed in a very short time.....or both.

Why are GENUINE KOENDERS WINDMILLS and Electric Aeration parts superior to OFF BRAND parts?

  1. All Koenders Windmills parts (tower, tail and fan assembly) are hot dipped and coated with the highest quality galvanized finish. Others use a lower quality galvanizing process. The Koenders approach ensures that these product components do not prematurely rust or break. They are built to last decades.
  2. Koenders Windmills tower, tail and fan assembly parts are made from 18 gauge high quality steel which is die-form stamped for strength and consistency. Many of the parts used in higher stress areas are even a heavier 12 gauge. Other organizations who are promoting phony Koenders parts use lower quality, thinner steel.
  3. Koenders Windmills owns the rights to all of our state of the art dies used in forming Koenders parts. These dies are extremely expensive: tens of thousands of dollars per/piece. This attention to detail allows us to produce precision parts consistently, while maintaining proper fit and durability throughout the manufacturing process. Others use a low quality parts cutting and bending process which produces inconsistent, less durable and ill-fitting parts.
  4. Koenders Windmills and EL-2 electric aerators use a diaphragm style compressor. These diaphragms require periodic replacement. A genuine Koenders diaphragm repair kit is U.S. made from a high quality Garlock, reinforced rubber blend material. This Garlock diaphragm material is the best material available and maintains proper strength and stiffness even during extreme heat or cold conditions. Many customers report a 8-10 year diaphragm lifespan from a genuine Koenders diaphragm. Others use a flimsy low quality rubber which is thinner, has little strength and a short lifespan.
  5. Inside every Koenders Windmill and EL-2 electric aerator are several small valves. These valves are the diameter of a penny. Although they are small, these check valves have a very important role. If these valves do not operate correctly, the compressor simply will not work. This type of valve was readily available some years ago as they were used for other applications. But today, Koenders Windmills is the sole manufacturer and end user of this style of check valve. Koenders has upgraded the original valve and replaced the rubber insert with (1.5 mm double skinned nitrile butadiene with cotton weave) which is much stronger and longer lasting. Rubber tends to crack in heat, cold and moisture and nitrile is one of the strongest rubbers available on the market so longevity is increased substantially.

We do not sell these valves to other suppliers. Therefore, if other suppliers offer them for sale the valve is most assuredly from VERY OLD STOCK and the rubber is of low quality.

Be careful when ordering replacement parts for Koenders Windmills and Electric Aeration products.

Koenders will not be held liable for customers who buy KNOCK OFF products. We have filed complaints with several government and consumer bodies, however, we are being told that due to our success and over 90% market share in this industry it seems to be a difficult issue to enforce because many of these groups are changing little items or letters on the product names to get around copyright infringement laws.

To avoid issues - Order direct from Koenders Windmills or Koenders Waters Solutions or Order from an authorized Koenders Windmills or Koenders Water Solutions Dealer.

How do you know they are Authorized Koenders Dealer?

Dealers will indicate prominently on their websites that they are authorized Dealers. If they do not, then they are not an authorized dealer and are not selling Original Koenders Windmills and Koenders Water Solutions parts. You will find that many of these phony Dealers will advertise under our brand name so look for Authorized Dealer of Koenders Windmills or Koenders Water Solutions on the top of their web page.

For Sales, Support or Customer Service please call toll free 1-888-777-4933 or 1-877-888-7707 or fill out our locate a dealer request form.


SINCE 1988

Fountain Sale for U.S. Customers!

Featured Products

Nature's Pond Conditioner

Your pond is not only a conversation piece; it’s a statement about how you care. You’ve invested in a pond because you love and re...

From $39.95


Click the button below to view the installation and maintenance manuals and videos

View Manuals & Videos


3rd party study confirms that Koenders windmills have the best performance ratings in the industry!

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The algae initially covered around 40% of the pond. Only 60 days after being on the Koenders 3 Step Program, the algae hasn't come back. Needless to say I am impressed.

Fairley Carey, Yanceyville, North Carolina

When something sounds to easy to be true it probably is!!! That is why when I was told about Nature's Pond Care 3 step program and the fact that it would not be an overnight success but more a process I started to believe!!!

Jeff Eckhardt, Landscaper, Edgar, Nebraska

The water has never been cleaner. What a huge improvement to the past. The water does not smell and we don’t have to worry about clogged filters for the pond is clean and clear now. Great products - thanks!

Gary Nervas, Langenburg, SK

Nature's Pond Care Program Works Great!! Over 7 years ago we started using your Nature's Pond Care program. Our Pond has been clean and clear ever since. As for our windmill aeration system. It aerates the pond all year round. Great product and it costs us nothing to run.

Sheldon Andrews, Shediac Cape, NB

Your Products Never Stop Working! We installed a Koenders Windmill Aeration system way back then and have never done a thing to it. It has been an extremely reliable and effective product and we are very happy with the results.

Judy White, Marysville OH

Nature's Pond Conditioner and Koenders Windmill Aeration - a truly effective combination! Every year since, we’ve used your pond conditioner in combination with the Windmill and it works great!!!

Earl Karns, Kensington, Ohio

Since installing our windmill aeration system we have never had a fish kill. The other benefit of having our windmill aerating our water is that it helps keep the water healthy and clean.

Joe Blandford, Lowell, IN

I just want you to know what a joy this windmill has been to own...for its durability and how it improves the health of my pond. It's been standing here 7-8 years and I've done nothing to it.

Dennis Rex, Auburn, NY

Our Koenders Windmill "Works Like A Champ!!!" Within 90 days we started seeing our pond clearing up. Our pond is now stocked with bass, blue gill, crappie and trout and the windmill aeration has done a fabulous job of keeping these fish healthy and clean.

Matthew Petersen, Yakima, WA

We had some extremely windy days this past winter and our windmill is still standing tall. We are very happy with our purchase and we trust in our Koenders windmill to keep our pond healthy and our fish alive!

Micheal Carroll, Delta, OH

Besides routine maintenance on the diaphragm we haven't had to do anything to it. The windmill keeps a hole in the ice for the fish throughout the winter and we haven't experienced any more fish kills since installing!

Rob McClure, Carrollton, OH

Last year we conducted a study on the farm. On one pond we followed your Nature's Pond care program by installing a Koenders Windmill Aeration system and treating the water with Natures Pond Conditioner. We did not do anything to the other pond. The difference between the ponds was miraculous!!!

Mike Deobald, Stone Barn Farm, Hodgeville, SK

We found that the windmill was very easy to assemble and were quickly pumping oxygen into our pond! One of the best things that we have found about our windmill is that we haven’t had to perform any sort of maintenance in the entire 15 years that we have owned it!

John Modra, Griffith, IN

We have 2 ponds about 20 years old, and about 10-12 years ago we decided to purchase a Koenders windmill aeration system for our smaller pond. It has honestly been one of the best things that we have ever bought! If you follow the directions and be sure to anchor it down properly it works absolutely perfectly.

Eric Lewis - Bloomer, WI

My uncle had recommended that I try Nature's Pond Conditioner as it had worked wonders for his pond and I am SO glad he did, the Nature's Pond Conditioner works great! I went from having an algae covered pond to almost no algae.

Mark Riley - Villa Ridge, MO

The fish have always stayed healthy and we have never had a fish kill! Our Koenders windmills have been working amazing and they just keep running like a champ. The only maintenance that we have done is simply changed the diaphragms on them every 7-10 years. I will stand behind your products no matter what. They last forever!!.

Tom Rowe - Britton, MI

That is one reliable windmill! That same windmill is still turning today pumping oxygen into our pond to help keep the fish healthy and the weeds and algae to a minimum. The windmill has never let us down and is quite attractive to look at. We love it!!

Steve King - Hamilton, IN

We are extremely happy with the quality of our windmill and how worry free it has been. We haven't had to do any sort of maintenance or repairs on it in the entire time that we have owned it. It seems to effortlessly pump air through the two airstone diffusers keeping our fish healthy and water clean!

Kay - Oshkosh, WI

We chose to work with Koenders Water Solutions Inc and have been following their Nature's Pond Care program for the last few years with outstanding results. Its been a real pleasure working with Koenders and we look forward to continuing our partnership.

Gene LeClair - Parks, Bldg & Grounds Ops Mtce (Core Parks Infrastructure) - City of Ottawa, Canada

I am very pleased so far with the performance of my Koenders Windmill Aeration System. It works perfectly all of the time. It turns smoothly, it pumps smoothly, it is great to look at, and I have never once had to service it at all!

Matt Hall - Brooklyn, MI

Our pond remains healthy and clean and we have never had a fish kill during all these years. We are very satisfied with the performance of our Koenders Windmill and has certainly lived up to its expectations.

Jack Mueller - Seymour, WI

About 30 days after pouring in Koender's Nature's Pond Conditioner and getting the Koenders double diaphragm aeration windmill set-up and working, the water cleared right up, my pond water is clear now, it was phenomenal!

Bernie Gorski - Harrow, ON

Our favorite part is to watch them catch fish from our pond and then clean them and cook them over an open fire. We are so happy with our Koenders windmill that provides our fish with the oxygen that they need to remain healthy, growing and reproducing.

John Barnes - Hillsboro, KY

We stood the windmill back up, and still to this day it is working the same way it did when it was new! We are very pleased with the simple operation and efficiency that we get from our Koenders windmill aeration system.

Raymond Heinlen - St. Johns, MI

We have had a Koenders windmill up and running for nearly 20 years. It has been the best way to provide oxygen to our pond that is close to 2 acres in size. When we stocked our pond with fish, our Koenders windmill aeration system never failed us.

Kyle Rudolph - Joplin, MT

We really enjoy our Koenders windmill, it looks beautiful in our yard next to our pond and we have gotten many compliments on it. Before assembling it I just spray painted the blades and tail with Tremclad primer and paint and it is holding up really well to the elements.

Angelina Grimson - JCalgary, AB

We installed one of your Koenders Windmill Aeration Systems over 15 years ago. We use it to aerate our 2 acre fish pond and it has done everything it was promised it would do. Since installing this windmill we have never had a fish die off and it has been working amazing year round for all these years.

John Brickner - Auburndale, WI

I have owned a Koenders Windmill for over 10 years and it has been working really well ever since I installed it!!! Not only have we saved money on electricity by using this windmill to aerate instead of electricity but we have never had to do anything to it.

Dale Conner - Park Hills, MO

I am Happy With Product, Real Happy!! We have been aerating our fish pond with a Koenders Windmil for over 20 years. The windmill aeration keeps the fish healthy and pond clear – you can see down 2-3 ft deep into the water.

Fred Green - Troy, OH

We installed two of your Koenders Windmill Aeration Systems over 15 years ago to help pump oxygen into our trout ponds. They have been running just like the way they were the day I installed them.

Mike Short - Cedaredge, CO

Its always tough being the leader in the market because these types of companies try to grab on to the success that you have created!! Thanks again for a really great product!!

Bob Hassen - Swanton, OH

We installed a Koenders Windmill Aeration System about 10 years ago on this pond and our water is in beautiful condition. This whole time we have never once had to do any maintenance to the windmill so it has definitely impressed us and lived up to our expectations!

Steve Raney, Raney Ranch Retrievers - Santa Ysabel, CA

We installed one of your Koenders Windmill aeration systems about 10 years ago to keep our fish alive in a 2.5 acre pond we have on the farm. Never had a fish kill since and this windmill has helped both keep our pond water clean and fish healthy.

Brian Wade - McGregor, IA

During this six years we have lubricated the pivot tube once and nothing else. It has done a fabulous job of getting rid of the algae and weeds. We can now see right down to the bottom of the pond and the water is so clear its like an aquarium we can even see the fish swimming in the water.

John Harbom - Caledon, On

We have been using Koenders Windmills to aerate our surrounding trout lakes for almost 30 years. These windmill aerators have kept our trout healthy and strong during the both the cold winter months and hot summers.

Keith Day, Kyle Fish and Game League - Kyle, SK

The Koenders HD 250 Electric Aeration System works really well to keep our sprayer nozzles from getting clogged up with algae, we are very happy with it. This saves us time and money.

Eric McPeek, Farmer - Coronach, SK

We purchased the Koenders HD250 Electric Aeration System and it works great. As a result of using It we now have the best water quality we have ever had! The odor from the pond has also been significantly reduced.

Hank Klok - Picture Butte, AB

Cranberry Farmer Uses Koenders Windmill Aeration Systems for Almost 20Yrs Maintenance FREE! I am a cranberry producer in Wisconsin and we have been very impressed with the results from our Koenders aeration windmill, it has done everything we had hoped it would.

Lewis Fader, Selz Cranberry Marsh Inc - Warrens, WI

Koenders keep our 6 Million Fish Healthy each Year!! Its cost, reliability and performance has been far superior. You can really tell that your company is the innovators of windmill aeration systems.

Randy Roeseler, Roeseler Fish Farms - Juneau, WI

The windmill has been working very well – we installed it in the summer to help reduce the sludge on our beach area at the cottage. Another one of the cottagers on the lake have done the same thing with successful results so we have decided to do the same thing.

Annette Loebach - Lac Sinclair, QC

Koenders Windmill Aeration is Keeping Our House Water Clean!! We have a single diaphragm windmill with two diffusers controlling the algae in our pond. It has worked wonderfully over the years.

Larry Weber - KS

Our Koenders aeration windmill is working great to keep our water healthy, doing the job it's supposed to do. We have 2 air diffusers connected to our windmill. After installing our Koenders windmills I would say the water quality and clarity has increased a minimum of 50%.

Brogowski, Gene - Clarence, NY

The Koenders windmill was a great purchase, you guys have a great product, low maintenance, in fact I didn't have to even change the diaphragm and check check valves on my windmill aerations system until my 12th year of owning it. It costs practically nothing to maintain.

Barber, C - Oxford, NY

We Love our Windmill and great Customer Service!! Our water is clearer and our fish seem livelier and our ducks seem to like it too. Everyone we have had contact with at Koenders has been extremely courteous, friendly and knowledgeable and it is a true pleasure doing business with y'all.

Jayne Ard - Latta, SC

I love my Koenders Windmill, it works great. It definitely keeps the water cleaner. I have one Koenders aeration windmill that I put in between 2 of my ponds and it does a great job of aerating them both.

Dennis Barlow - Newcomerstown, OH

I have to tell you that we believe your windmill has helped the health of our pond tremendously. We've had it for about 6 years and only recently had to replace the diaphragm. We really enjoy our pond now and go swimming in it almost every day during the Summer.

J Bolger - Vermont

We are just very pleased with our Koenders Windmill Aeration system, very pleased! We didn't realize how much wind we had until we got our Koenders windmill, the slightest breeze the windmill is aerating. The water has cleared up, the fish are happy; we are catching bigger fish.

Jayne Ard - Latta, SC

Our Koenders windmills is working really well, no complaints. In fact, our bottom up aeration system from Koenders are growing these fish to be so big and healthy that just the other day one of our friends were fishing at the pond and the blue gill fish they caught was so big it almost pulled them in the pond.

Virden Ault - Kenton, OH

We have been using a Koenders Windmill to aerate our 1/2 acre pond for over 15 years. We raise 200-300 gold fish per/yr and my sons sell them to customers and make a little school money. Its amazing how little wind this windmill needs in order to get the bubbles going in our pond.

Richard Hurry - Grand Rapids, OH

In 1999, we made the switch to aerating our septic system with a Koenders windmill. We just recently purchased a maintenance repair kit for $ 69.95 to overhaul the pump - not bad for 16 years of operation. I cant imagine the amount of money that I have saved on electricity and replacement of pumps.

Kenneth Yoder - Hartville, OH

Our Koenders Windmill Went Up Like A Dream!! The windmill has been virtually maintenance free for over 7 years now and the paint and everything looks outstanding - still looks brand new!!

Tracy Lectka - Oakley, MI

We installed 2 of your Koenders Windmill Aeration Systems over 10 years ago on 2 of our 3 sewage lagoons up in Thompson MB. Five years ago we installed a 3rd windmill aeration system for our #3 settling pond. These aeration systems have done an amazing job.

Barry Michaluk, Manitoba Conservation Group - Thompson, MB

Our Koenders Windmill Aeration System has done a wonderful job of aerating our 2 acre recreational pond for the last 12-15 years. Until recently, we have never done a thing to this windmill, It has kept the pond water clean and the fish healthy ever since we installed it.

Curt Schurman - Atlington, IA

Since I put my Koenders Windmill Aeration System in 6 years ago the difference in my pond water is night and day. I love my Koenders Windmill.

M Conrad - PA

We have owned our Koenders Windmill Aeration system for over 10 years and until recently have not had to do one thing to it. We just love the the quality of your product and it has done a fabulous job in keeping our pond water healthy and clean.

Robert Saxon - Rehoboth, MA

I have three Koenders windmill aeration systems, each one aerating a different fish pond. My neighbor also has 2 of them installed on his fish ponds. Ever since we installed these units we have never had fish kill offs, we have also never had to do any maintenance on these windmill aeration systems.

Chuck Westholter - Clear Lake, MN

I have seen such an improvement in the pond since doing all the repairs and treating it with Natures Pond Conditioner. This system is about 20+ years old and doesn't look like it has had much maintenance to it but is working very well. Thank you Koenders!!

Lyle Kummer - Sioux Falls, SD

I purchased a Koenders aerator windmill in 2006 for a 1/3 acre pond here close to Houston. It has worked perfectly for all these years. I would definitely recommend a Koenders windmill aerator to anyone who has a pond in order to keep it healthy.

Paul Jozwiak - Rosenberg, Texas

Done Nothing to Our Windmill For 15 Years!!! Our windmill has been aerating our 1/4 acre pond for over 15 years and it has been pretty well care free for this whole time. We swim and fish in our pond and the windmill aeration system has done a marvelous job of keeping the water clean.

Lewis Forrest - Arnprior, Ontario

I purchased a 16' windmill over the July 4th weekend and it's been up and running for about 3 weeks now. I was really impressed how well engineered it was and how everything fit and went together. So far I'm really impressed , happy and satisfied with your product. I'm looking forward to many years of reliable service from it.

Rick Wing

We have owned one of your windmill aeration systems for over 16 years and it has done a marvelous job of keeping our pond water clean and algae free. Really like the look of your windmill and the fact that it does a reliable job of keeping our water clean is a bonus!!

Mrs. Kenny - Mono, Ontario

We installed our Koenders Windmill in 2006 – it is used to aerate our 3/4 acre pond that is about 11 FT deep. Our pond is stocked with Bass, Blue Gill and Perch. The windmill has kept the fish healthy and alive during all seasons of the year, it also helps keep our pond water clean. Your product works great and we have never had a problem with it during all these years!

Bob Kocourek - Brillion, WI

We have been using a Koenders Windmill for over 7 years to aerate one of our settling ponds for compost. It has worked extremely well in eliminating the odors from the water and we have been so impressed with the results that we ordered 3 more Koenders Windmill aeration systems for our other 3 ponds.

Terrence Boyle - Antigonish, N.S.

I have to tell you we just love the fountain and the light kit. People are in awe of the light show at night coming from our pond. The fountain is so eye catching and relaxing to watch and listen to. We are so glad we added it to our windmill system. The windmill is great too and those hinges make raising and lowering the windmill a snap.

Mike Fletcher - Marintown, ON

We had used one of your pond aeration windmills for about 7 years on our dairy farm. We really noticed a difference right away, our milk production increased dramatically. We never had to do any maintenance to the windmill in the 7 years that we owned it. I highly recommend it to anyone.

Anne Friesen, Dairy Farm - Macgregor, Manitoba

We have been quite happy with our windmill aeration system from Koenders. It works well in aerating our 3-4 acre fish pond both in the summer and winter. For as large as our pond is the windmill has managed to keep our fish alive and an area water open during the winter months. Our pond is one of the cleanest in the area.

Brent Dennis - Troy, PA

We installed our windmill over 10 yrs ago and it is still working well. We primarily use the aeration to keep our fish alive, our pond is full of bass. Down here in Texas we are having one of the worst droughts ever and despit the hot temperatures, lower than ever water levels, our fish are thriving. Since installing our Koenders Windmill we have never had a bass die.

Joe Fuller - Gunter, TX

Koenders Windmill Aeration Works Great on Our Sewage Lagoons!! We bought 2 of your aeration windmills about 4 years ago to treat our sewage lagoon. They have worked great to get rid of the fouls smell and algae that we were having trouble with. We are very satisfied with the Koenders aeration windmills.

Huguette Lutz, Chief Administrative Officer - Town of Carlyle, SK

"Your aeration windmills have worked great to keep one of our municipal ponds open during the winter, maintaining it odor free and fish healthy. We purchased it about 3 years ago and haven't had any problems with it, we actually plan on using one your windmills for our sewage lagoon holding cells, to get rid of the algae."

Sandy Hintz, Mayor - Town of Wapella, SK

"We have been a Koenders Windmill customer for 25 Years. Our dugout water is used for our farm home and the windmill aeration keeps the water clean all year round. It is especially helpful during the winter months - we used to have smelly water in the house, but with the aeration we do not get that rotten egg smell in our water anymore."

Peter Starko - High River, Alberta

"Koenders Windmills are Built Tough!! We have owned our 20' windmill since Feb 2008, the mill has never needed maintenance. During Hurricane Ike we had to evacuate and I forgot to lower the windmill before we left. When we came back the neighbourhood was damaged but the windmill was fine and still pumping air despite being hit by 90+ Mph winds."

Mike Morgan - Orange, TX

"Our windmill is about 20 years old, during all this time we have only done maintenance on it twice. We have been using the windmill to aerate our fish pond. The aeration system has prevented any fish kills from ever occurring, even during the severe drought that we had in 2011 we didn't even lose a fish."

Marty Baecker - Rogers, TX

"We installed our windmill over 12 yrs ago and it has run practically maintenance Free. It has been doing a wonderful job in keeping our pond water clean and Fish healthy,Bass, Blue Gill and Catfish. Looking forward to trying your Natures Pond Conditioner - what an excellent alternative to the Pond Chemicals that are out on the market."

Paul Hutchins - La Motte, IA

"We Were able to use our Pond Water FOR Drinking!! People are amazed at how clean our water stays and come to visit our windmill system all the time. I am only now having to replace the maintenance repair kit in the compressor."

Bill Thompson - Wallacetown, Ontario

"We have owned the Koenders windmill aeration systems for a couple of years now and we have seen a significant improvement in the quality of our golf course pond water. The Koenders windmills have kept our water clear, algae free. We are very happy with the product, even more so that we don't have to use any dangerous chemicals to keep our water clean."

Carla Clarkson - Brandon, MB

"We have been using your aeration windmills for 2 years now and they definitely get the job done, in fact we have 6 Koenders windmills at our golf course. They keep the algae away and really that's all we have ever wanted. I would definitely recommend this method of keeping golf course ponds clean."

Matt Iannetta - HoneyBrook, PA

"Before installing your windmill we had fish kills and the pond was completely covered in Algae. Now with the Koenders windmill we haven't had any fish kills and the pond is now clear. Golfers are always interested to see how well the windmill is working, especially when you get 10 mph and higher winds, it really starts bubbling."

Darren Binggeli - Whiteman Air, MO

"Our windmill aeration system by Koenders was installed 20 years ago on our 1/2 Acre fish pond in Ontario. It has kept our pond open during the winter months and our fish healthy all year round. It has been a very effective and reliable way for us to do it for all these years."

Joan Chikinsky - Metcalfe, Ontario

"We have been using the Koenders windmill aeration systems to treat our 1 acre sewage lagoons for about 2 and half years now, we have been amazed by the results. We couldn't be happier with your product."

Sean DeHavilland - Mission Hills Community Services District

"We run a Camping Resort called Cozy Corners and installed a Koenders Windmill 15 years ago to keep our fish healthy and our pond clean. Your windmill aeration system works awesome!!! It keeps the moss off the pond and our fish alive. It has worked problem free for all these years."

Randy Bramlett - Clinton, MO

"19 Yrs with our windmill aeration system by Koenders and never had to perform maintenance except for one little screw adjustment. Amazing that for all these years I have never had to perform any maintenance - this unit has been pumping for all this time. Our fish also enjoy the added oxygen that the windmill gives them."

Wayne Sigsworth - Smithfalls, Ontario

"I built my own tower and mounted a Koenders double diaphragm windmill head with no trouble at all 3 years ago. I am able to aerate my minnow pond with three air stones and the past 3 years I've not experienced one fish kill. I run it year round and it works great."

Robert Marek - Cadott, WI

"We installed our Koenders Windmill over 14 years ago at the suggestion of the guy at the local Fish Farm. We have never had a fish kill. The pond also looks a lot nicer since we installed the windmill aeration. This product has been maintenance FREE for all this time eventhough they told us that we would need to do maintenance."

Terry Snyder - Bryant, Indiana

"We installed our windmill aeration systems on our Waste Water Treatment ponds in 2009. The windmills are being used to help clean the waste water so that we can re-use it in our manufacturing process. The product is performing as per expectations and we are happy that we made this choice for lagoon aeration."

Karl Smith - Innophos Corporation

"We have been using a Koenders Windmill aeration system to aerate our Farm Fish Pond for over 10 Years and it works great. We put 500 Trout into this pond each year and the windmill aeration keeps the water clean and algae FREE. It also keeps the fish healthy all year round. Thanks for helping make sure our fish are kept so healthy."

Irwin Gatzke - Warman, SK

"Koenders has helped us keep our pond water clean and welcome life like frogs and minnows abundant through our use of your Natures Pond Conditioner and the aeration windmill."

Bob Morrison - Bethany, Ontario

"We put it up in 2002 after we experienced a significant fish die off in the spring. Since putting it up, our fish are very happy. I am looking forward to your Pond Conditioner to see how it works."

Kathy Hutton - Hartland, MI

"Unbelievable!!!!! I was looking through my invoices from when I purchased our Koenders Windmills and it is exactly 12 years to the month and we have not done anything to them. We installed 2 of your Koenders Windmill aeration system to aerate our 18 Ft deep fish pond. The windmills keep the fish healthy and the algae and weeds down. Thanks for a such a great product."

Raymond Rady - Homestead County, OH

"Our Koenders Windmill aeration systems is one of the few things in life that you do not have to do a thing to once it is up and running. We installed this system over 7 years ago and it has done everything it promised and more. We have a 1/2 acre trout pond on our acreage and this windmill has kept the pond clean and fish healthy during all seasons."

Ron Hepperle - Millet, AB

"We have been using your windmill aeration system for 10 years and it has been maintenance Free. The Koenders Windmill Aeration system has kept our fish healthy and happy, we have perch that are over 13 inches long. This aeration method has been an excellent source of oxygen for the water and using this windmill allows us to do it with no energy costs. "

David Mitchell - Abrams, WI

"We bought a Koenders Windmill aertion system over 13 years ago and its kept our pond water nice and clean. We have never done a thing to our windmill, not even any of the maintenance that Koenders recommends, this must be a new record for product neglect and one that keeps working despite its lack of care. "

Tim Rokosz - Freeland, MI

"We have owned our windmill aeration system for almost 20 years and amazingly have not done a thing to it for all these years. It has kept our cattle drinking pond algae and weed free. We pump water up from this pond to a holding tank for our cattle to drink from. "

Dean Dowling - Swanton, OH

"We have a spring fed recreational pond about 1 acre in size that is full with fish. About 12 years ago we purchased our Koenders Windmill aeration system to ensure our pond does not stagnate. The windmill is doing a marvelous job of keeping our fish alive and the pond water clear. During the winter months it keeps a hole open in the ice to ensure the pond can vent off the gases caused by the decomposing of leafs and other matter, another key to keeping our fish healthy all year round."

Vincent Luczak - Fife Lake, MI

"We have been using a Koenders Windmill aeration system for over 7 years to aerate my 1/4 acre recreation pond in my back yard. It has been maintenance Free and the fish, frogs, and birds love it. I have 2 diffusers running off the one windmill and they are in about 16 FT of water. Thanks for a wonderful and reliable product. "

Gerhard Epp - Wheatly, Ontario

"I have owned my Koenders Windmill for 17 years and it has been working wonderfully ever since. A few years ago we had a terrible drought down here in Texas, our pond water level dropped from 9 Ft to 3 Ft. All the other pond owners in the area lost their fish, but we didn't lose any. I credit this to our Koenders Windmill Aeration System."

Dennis Scott - Livingston, TX

"My mother bought our windmill way back and it has been in service for over 20 years. It keeps my pond really clean and the fish healthy. We have never done anything to this windmill. It just keeps on working, in all seasons and in all winds. Quite amazing."

William Baker - Dillsboro, Indiana

"I am happy to say that since we installed the windmill we have had no issues with our pond. Our fish are healthy and we have clean pond water. We have not serviced the windmill for all these years, it just keeps on working. Great product!"

Mike Hinson - Troy, ID

"We have been very happy with our windmill. For over 10 years we have been using your windmill to pump water to irrigate our gardens and to aerate our ponds. Koenders you have built an excellent product that works very well. "

Keith Barrett - Plainfield, Ontario

"I would recommend the Koenders aeration system to anybody that is looking for something that is maintenance-free and does a good job. Absolutely."

Mark Pehlemann - Cash Crop Farm, Port Perry, Ontario

"The Koenders windmill aeration system is a fairly simple and beneficial way to achieve aeration for your pond and it gives you a good amount of oxygen into the water which helps prevent algae growth."

Karen Jeffrey - Fish Farm, Erin, Ontario

"Before installing our windmill aeration system we had experienced fish kills during the winter months. Our Koenders Windmill Aeration system has kept our pond open and fish healthy during the winter months and we have never had a fish kill since."

John Veriha - Marinette, WI

"I have had one of your Koenders Free Air windmills installed on our 2 acre fish Pond for over 8 years. Since we have installed this windmill aeration system I am pleased to say that we have never had one fish die."

Scott Ites - Iowa Falls, Iowa

"We have owned our windmill aeration system for 14 years and are amazed by the incredible job it is doing in keeping our pond healthy and clean. Our Koenders Windmill has removed and kept out 99% of the weeds and algae in our pond."

Robert Bergenstock - Lycoming, NY

"The combination of windmill aeration and your pond conditioner has cleaned up my pond and provided me with a pond maintenance program that is environmentally friendly, economical and extremely effective."

Jason Wilcox - Bartlett, NE

"You were right on about your product advice. I have been having problems with my pond for years. It has looked like the before picture every summer until this year. Thanks to you guys the combination of aeration along with your environmentally friendly bacteria and other ingredients has cleaned up my pond in record time. No more chemicals for me"

Jeff Stevenson - Katy, TX

"I started using Natures Pond Conditioner 2 years ago for my pond and it has worked better than any other treatment. Our pond gets a lot of sunshine and Natures Pond Conditioner not only shades it from the sun but it also provides it with the extra supplements it needs to keep it clean."

Lenore Smith - Bowmanville Ontario

"I could not be happier with the results, in 2 months you can see a marked improvement in the water quality. We have already had 2 ducks & a family of water fowl take up residence ... A happy customer"

Alan S. - Australia

"I would recommend the Koenders aeration system to anybody that is looking for something that is maintenance-free and does a good job. Absolutely."

Mark Pehlemann - Cash Crop Farm, Port Perry, Ontario

"Before installing our windmill aeration system we had experienced fish kills during the winter months. Our Koenders Windmill Aeration system has kept our pond open and fish healthy during the winter months and we have never had a fish kill since."

John Veriha - Marinette, WI

"I have had one of your Koenders Free Air windmills installed on our 2 acre fish Pond for over 8 years. Since we have installed this windmill aeration system I am pleased to say that we have never had one fish die."

Scott Ites - Iowa Falls, Iowa

"We have owned our windmill aeration system for 14 years and are amazed by the incredible job it is doing in keeping our pond healthy and clean. Our Koenders Windmill has removed and kept out 99% of the weeds and algae in our pond."

Robert Bergenstock - Lycoming, NY

"We have been using your windmills to aerate our 11 Acre Fish and Irrigation Pond for over 7 years. We have several of your Koenders Windmill aeration systems on the pond and it has served to keep the water algae and weed free. This assists us in irrigating our corn, hay and alfalfa fields by ensuring the irrigation pumps do not get clogged up."

Colby Edwards - University of Missouri

"We have been using your windmill aeration system on our 3 acre Fish Pond for over 16 years. It may be hard to believe but we have never had an issue with the windmill. Never taken it down for any maintenance, never even done any maintenance on it."

Charles Casey - Lacon, IL

"When we bought our windmill over 11 years ago there were none of these units around. Now, anyone in the area who has a pond also has a windmill, 50-100 of them in the region. A few of the neighbors have installed other brands but they clearly do not work as well as the Koenders Windmill which is what almost all of the pond owners have."

Kevin Armstrong - Ashton, Ontario

"We purchased a Koenders Electric Aerator - the EL2 unit over 10 years ago and it has been running 24/7 ever since. The only maintenance we have ever had to do is replace the diaphragm in it once. It keeps our pond/dugout water sparkling clear and is the water that we use for our cattle to drink from."

Alan Lewis - Taylor B.C.

"By placing 5 separate windmill systems on various ponds, the City has cost effectively solved the problem. The windmills have now been working for 1.5 years and the hydrogen sulfide smell has not been an issue once. Also, water quality is slowly improving. Overall, Koenders Windmills have been a great, cost effective solution for the City of Prineville."

City of Prineville, Oregon

"We have been using your windmill to aerate our fish pond for over 10 years. The year before purchasing the Koenders Windmill we had a large fish kill, never happened since we installed our windmill aeration system. It works very well in keeping the pond water open in the winter and the water clean in the summer."

Dirk Emde - Hanover, Ontario

"We bought our Koenders Windmill in 1990 and replaced the first diaphragm around 10 years later. Here it is 2013 and I am just replacing it again. Other than greasing the tower top every year it has needed nothing else. We have bass, bluegill and perch in our pond and the windmill keeps the water in real good shape and our fish healthy."

F Green - Troy Ohio

"Over 12 years ago we installed a Koenders Windmill to pump air into our 3/4 acre Brim and Bass Pond. Since installing the windmill we have had no issues with either it or the pond. Louisiana is not known for high winds, however, this windmill has worked so well in low winds that it has been an ideal solution to keep our fish healthy and our pond clean."

Kevin Bernard - Rayne, LA

"We are proud owners of 3 X Koenders Windmills. Two of which we have owned for 7 years - these units are aerating two of our bigger fish ponds. The 3rd Koenders Windmill is aerating our gold fish pond and has been doing so for over 14 years. These windmills have been working with no issue for all these years and they are so much fun to watch!!!"

Nancy Renfrew - Plummer, ID

"Just wanted you to know that your product is one of the few that I have ever bought that works the way it says it will. Nowadays, you never know what your going to get but I am so happy with your Koenders Windmill aeration system that I just bought another one for my other pond."

Chris Vice - Georgetown, ILL

"We have been a proud owner of an original Koenders Windmill for over 20 Yrs. It has aerated our Farm pond water that is used for both livestock and home use. By aerating the water we have avoided the smell that can come from these prairie ponds in the hot summer and cold winter months."

Dwayne Johnson - Tribune, SK

"We have had our fish pond for just over 5 years. The first few years we tried all sorts of different pond treatments that you find at the various retail stores. Then we came across Natures Pond Conditioner via a web search. We figured that we had nothing to lose at this point and for the last 3 years we have been using Natures Pond Conditioner. We Love IT!!"

Lenore Smith - Bowmanville, Ontario

"It may sound incredible but its true, we've had our windmill for 14 years and 10 years ago we had a straight line wind come through our property . It blew down my pull barn and ripped half the roof off my house. My windmill was still standing, didn't hurt it a bit. Should have known then that it would run for 14 years with no maintenance at all."

Audley Craig - Britton, MI

"We have been using Koenders Windmills for almost a decade to aerate two of our 1.5 acre farm ponds. They have worked real well, so well that my neighbor, Wally Walldrop, installed one for his farm pond a few years ago. We are so happy with the product that we just purchased two more 12 FT Koenders Windmill Aeration systems for our other 2 ponds."

Linden Rollyson - Dahinda, ILL

"We have used your windmill to aerate our fish pond for the last 15 years. This windmill is so sturdy and durable that is has even survived 3 hurricanes in the last several years with no damage. If anyone is every worried about the strength and sturdiness of these windmills and towers in severe storms tell them not to. They are an amazing product!!!"

Kevin and Darlene Norman - Youngsville, LA

"Our pond was brand new when we built it 14 years ago and one of the first things we did was to install a Koenders Windmill Aeration system. Our pond is 1 acre in size and we stock it with Rainbow Trout. It has kept the water clean and the fish healthy. The combination of Fish and Air is what has kept this water so clean, with no algae or sludge for so many years."

Neil Baird - Sing Hampton, Ontario

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