Nature's Pond Care by Koenders Water Solutions Inc.


Many farmers and pond owners alike decide to stock their ponds with fish. Whether it be for recreation or profit, people can spend thousands on maintaining a pond stocked with fish and striving for the biggest catch. What could possibly be more devastating after all the time, money, and passion put into a pond, than experiencing fish kill. A fish’s fate depends on its environment, part of that is its food, something that most people focus on when they want to grow larger fish. But large fish are healthy fish. And healthy fish need a healthy environment. This article gives you all the tools you need to create a healthy environment for fish, from creating the right balance of fish breeds, maintaining healthy oxygen levels, feeding, vegetation, and structure of the pond.

Choosing Fish for Your Pond

Pond owners typically like to stock ponds with fish they like to catch and eat.  You also need to keep in mind that the types of fish in the pond have to form a healthy balance. A balance must be met between forage fish and predator fish; in the right conditions, any breed can take over a pond if overstocked.

Our regionally licensed Fish Hatcheries that supply our fish provide recommendations, and we have suggested fish types and amounts of each in our order guides depending on the size of your pond. Each state or jurisdiction also has certain regulations on what can and cannot be stocked.

Choosing an Aeration System for Your Pond

The main cause of fish kill is lack of oxygen in the pond. A pond can become depleted of oxygen for many reasons. Nutrient pollution which leads to overgrowth of weeds and algae results in amounts of decaying organic matter that a pond can’t keep up with. When organic matter dies it is beneficial bacteria’s role to consume the matter and aid in the breakdown process. Bacteria are living organisms that require oxygen, and use up a lot of it when they are working hard, which can quickly deplete the environment of oxygen.

Oxygen is in shorter supply during the hot summer months, however, oxygen also becomes scarce in a pond in the winter. If a pond freezes over and no sunlight can enter the body of water; photosynthesis, the process of which plants use energy from the sun to create oxygen, cannot occur.

Another cause of fish kill in the summer could be due to stratified pond water. In the summer, the top layers of a pond are warm and the bottom of the pond is cold, this is called stratification. The cold water at the bottom has less oxygen than the top layer, and fish spend most of their time in the top layers. If a summer storm hits the pond; wind and rain can stir up the pond, de-stratifying the water. When the two layers are mixed, the oxygen levels are lowered dramatically, and the shock can cause a fish kill.

The best way to restore a body of water’s oxygen levels is through aeration. Aeration helps decompose organic matter in water and provides the necessary oxygen levels for fish to thrive and remain healthy all year round.

There are two types of aeration systems; bottom up aeration and surface aeration.  Bottom up aeration is considered the most efficient way to aerate ponds and is found to be up to ten times more effective than surface aeration. For more on bottom up aeration CLICK HERE. Air is pumped down to the deepest area of the pond where a diffuser pushes oxygen into the water as fine bubbles increasing the oxygen levels of the water. Koenders Water Solutions manufactures windmills and electric aeration systems.  They are the world leaders in windmill aeration systems with over 100,000 windmills installed in over 23 countries. These units do not require electricity to run and will operate in almost any area of North America, even in areas that have average winds as low as 3-5 MPH. 

Conditioning your Pond

Using a natural pond conditioner can safely clean and clear the water at the same it can reduce muck and sludge on the bottom.  Clear ponds allow fish to see and consume insects floating on the top of water.  Reduction of muck and sludge improves oxygen levels, provides a healthier environment for fish to grow and thrive.   Nature’s Pond Conditioner is an example of a pond treatment product that contains a natural blend of beneficial bacteria and enzymes that are designed to both clean and clear the water and combat pond sludge and muck.  Most importantly it is completely safe to use with fish in the water, unlike some herbicides and algaecides that contain chemicals that can be harmful to fish and the people who eat them.

Shade the Pond with Pond Dye

Pond dye is not just to make the colour of the water look good on the surface. It helps to inhibit the suns rays from entering the depths of the pond. This not only keeps the water cool, but it also slows down plant and algae growth, by limiting the amount of photosynthesis that can occur.

Remove Unwanted Aquatic Vegetation

Removing unwanted aquatic vegetation is an important step in keeping the ponds habitat suitable for fish health. Too much vegetation can deplete the environment of oxygen that fish desperately need, but some vegetation is still required to help produce oxygen naturally if the pond is not being aerated. A balance must be reached.

Many turn to herbicides and algicides as methods to rid their ponds of vegetation. This may not be your preferred option with fish living in the waters, because of the harsh chemicals they contain.  With a simple weed cutter and rake vegetation can easily be removed in areas of the pond that need grooming, no chemicals required.  By physically removing the vegetation you are minimizing the amount of organic matter that decays and settles on the bottom of the pond.  You are also reducing the nutrient load in the water that is used for further algae and weed growth.   

If permitted in your region you may also consider adding Amurs.  Amurs are a type of fish that are very effective in consuming vegetation.  They typically take at least a year to mature, as they grow they will consume more vegetation.

Pond Structures or Cover for Your Fish

An important part of a pond’s production revolves around how much structure (fish cover) is in your pond.  The reason for cover is to help increase survival rates and thus reproduction potential.  When any type of fish hatches, they will need some place to hide and feed.  This will give a big boost to the survival rate of all species of fish.  The fry will go into hiding and find cover until they reach a few inches in size.  Giving little fish a chance to grow and reproduce will increase the pond’s population. 

Steve Fender, of Fender’s Fish Hatchery has built hundreds of acres of fish ponds over the years and tell us that the best type of cover is natural cover such as tree branches, small trees, pine trees, scrub brush, and brushy trees of any kind (stay away from anything thorny).  Try to place cover two to six feet out in the water (if placed too deep, the small fish will not go out to it).  By using natural cover you will invite insects and other living matter for your fish to feed on. 

Feeding Your Fish

Fender’s Fish Hatchery is the largest fish hatchery in the Upper Midwest and they suggest that pond owners who choose to feed their fish should consider doing so with pellets.  This can be great for the whole food chain. For example, larger fish size as a result from feeding can result in earlier breeding in forage fish like Bluegill, and excess food from feeding can enable organisms at the bottom of the food chain like phytoplankton to grow, affecting all organisms higher up. If fish are being fed with pellets it also means that there is less competition for food, which will increase health and reproduction in all species in the pond. A good example of successful supplemental feeding in an ecosystem is if there are catfish and bass in the pond. Because of the rapid growth of Catfish, they are very much in competition with bass. By using pellets catfish tend to become lazy and will feed off of pellets, leaving more room for bass to thrive in the environment. 

If you don't have time to go to the pond everyday or so, there are a lot of automatic feeders on the market that will do the job for you. If you do decide to start a feeding program it is important to feed your fish on a routine basis so that they can be trained.  Evenings are usually the best time to feed, around dusk.  Just like dog and cat food manufacturers, there are fish feed manufacturers.  Select quality feed - remember you are eating these fish so you are what they eat.  

Customer Reviews:

“I constructed my pond in the late 1980’s, and made it about 1/3 of an acre in size. We wanted it for fishing, recreation and swimming, so have stocked it over the years with a variety of fish. We noticed we would lose some of our fish each year during July and August. In 2006, we finally decided it was time to address that problem and we installed a Koenders Windmill Aeration System, and it’s been running fine ever since. 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

“We installed a Koenders Windmill Aeration System almost 20 years ago. Ourselves and everyone else around us were experiencing large fish kills and we wanted to put an end to it. Since installing our windmill, we have never had a fish kill. The other benefit of aerating our water is that it helps keep the water healthy and clean. We do get some aquatic vegetation so we used Nature's Pond Conditioner as well. Works well in combination with aeration and it’s all natural which is great so we don't have to worry about it harming our fish. Thanks for your great products and commitment to nature!” – Joe Blandford

“Koenders Windmill Aeration Systems Help Grow BIG and HEALTHY FISH! 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. So, I would say the windmill aeration system is working well, especially when a Blue Gill fish can do that!” – Virden Ault 


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