How to Keep Your Swimming Pond Clean?

How do I keep my swimming pond clean

If you have made your decision for a natural swimming pond in your garden a reality, it is undoubtedly also important to you to keep it clean so that your swimming fun is not clouded in the most real sense of the word after a short time.

The water in your pond is exposed to many different influences throughout the year. Rain, snow as well as autumn leaves in the fall.

With this article, we would like to give you an overview of what contaminants can accumulate in your swimming pond and what measures you can take to prevent and remove the contamination should it have occurred despite all precautions. You can always spot a change in the water by its coloration – it turns green, brown, or becomes cloudy.

Important Basic Rules for Pond Care

It is essential to follow some basic rules for a clean pond. First of all, no two ponds are alike. A garden pond is not the same as a koi pond or even a swimming pond. What is the right solution for one type of pond is the completely wrong approach for another. Each pond has its unique ecological balance, and thus quite different requirements for the necessary care.

It is also essential to know that pond maintenance is a continuously recurring task. Good pond maintenance will keep you busy throughout the year in varying degrees of intensity. Accordingly, it is also crucial to always be on the ball.

Necessary Equipment for Proper Pond Maintenance

Your absolute essential equipment for pond care includes a pond or algae scraper. A pair of pond scissors and a pair of pond tongs also make your work easier, as the tongs can be used, for example, to remove dead plant parts before they can sink to the bottom of your pond. This is because sunk material begins to rot. A consequence of this is siltation and algae formation. But you can read more about this below.

It is also essential to choose the right plants for your pond and cut them back correctly to counteract rampant growth.

Additional cleaning equipment, such as a professional pond mud vacuum, can also be a great help and make pond cleaning a breeze.

What Impurities can Occur?

Despite all preventive measures, it is impossible to avoid the fact that your swimming pond will need cleaning from time to time.

Green Water Occurs When Algae Multiply too Much

Algae will always form in your pond. However, this is entirely normal and also healthy for your pond. Algae are the primary source of food for many microorganisms. Besides, algae provide a sufficient oxygen content.

However, the water only becomes green when algae multiply very strongly in your pond. This is especially the case when large amounts of leaves, pollen, food for your fish, and their excreta end up in the pond. All these residues provide a large excess of nutrients, which accelerate filamentous algae and floating algae’s growth enormously. If also, the warm sun shines on your pond, the ecological balance is thrown into disarray. In extreme cases, the water can even tip over. This always happens when the pond’s oxygen supply and bacteria are higher than the oxygen supply via the surface.

To fight algae effectively and even prevent them, it is essential to clean and maintain the pond.

What Can You do Preventively to Keep Contamination Low?

You have it in your hands to keep your swimming paradise clean if you consider a few things that help minimize the level of contamination of your pond.

The coming points will help you prevent the pond from turning green and ultimately brown:

  • Regularly remove leaves, branches, and other debris from your pond.
  • Especially in the fall, protect the pond from incoming leaves, for example, by using a leaf net.
  • If you have fish in your pond, make sure to use a high-quality filtration system. This will help break down fish droppings.
  • Be careful not to over-fertilize the aquatic plants used.
  • Use gravel or particular low-nutrient substrates for planting, as these do not release nutrients into the pond, and avoid using topsoil.
  • To protect your pond from excessive sunlight, you can use a solar sail.

Brown Water Due to Mud in the Pond

In particular, mulm accumulates in any body of water. This is a decayed organic material, i.e., dead plant parts, microorganisms, bacteria, and trace elements. The mulm forms the precursor of sludge, which settles at the bottom of stagnant waters. The water gets a brownish color.

To eliminate such clouding of the pond, a desludging of the complete pond will help you. A professional mud vacuum cleaner can help you. With a special mulm vacuum cleaner, the mulm on the gravel surfaces can be removed, and with a special brush, you can free the foil surfaces from dirt very well.

The mud vacuum cleaner pumps the water out during such an action. If you have fish in your pond, it is advisable to move them temporarily until you have finished cleaning the pond. There are unique water recirculation systems, with which you can feed the pumped out water directly back into your pond. With such systems, however, a certain amount of contamination of the water always remains. Alternatively, you can, of course, refill with fresh water.

Especially in spring, you will find your pond rather cloudy brown. In the fall, leaves often get into the pond where they decay, and degradation products are washed out. In spring, only a thorough cleaning will help.

The Pond Water Is Milky Turbid

If the water appears neither brown nor green but somewhat milky and cloudy, this is due to microscopic impurities. These are not visible to the naked eye and mostly caused by algae and decomposition products of dead algae. Even a pond filter used in a natural pool does not help much with such impurities. Milky turbidity can also be of mineral origin and caused by lime, for example.

Microalgae can be clumped well with UV light. Due to the light irradiation, they attract each other and deposit on each other. In this way, a pond filter can also pick them up again. To be able to bring such light into them, you need special UV light equipment.

What Rules Apply to the Use of the Swimming Pond?

Make sure that even when swimming, you do not introduce unnecessary impurities into the water. You should never enter the pond creamed or oiled. It is advisable to shower off before swimming to avoid contaminating the water.

Do not allow pets in the pond to prevent them from introducing hair and dander into the water.

If possible, do not use fertilizers for the pond plants and make sure that you choose a low-nutrient product as early as the plant substrate selection.

What Possibilities Are There to Work Towards Clean Water Already When Selecting Plants?

Already when you create the pond, take note of which plants are in its vicinity. Strongly flowering or deciduous woody plants should better not be located directly at the water’s edge but some distance. Otherwise, they will introduce a lot of biomass into the water.

When planting your pond, also choose plants that are little helpers in keeping the water clean. Oxygen plants, for example, keep the pond free of algae and thus the water clear. When choosing, be sure to combine different plants that produce oxygen at other times of the year.

The roots of individual aquatic plants, such as bulrushes, water lilies, and duckweed, can also remove bacteria and other contaminants from the water.

Populate the plant zone with filtering plants, called repositioning plants, whose roots absorb and process excess nutrients from the water. A widespread plant used for this purpose, which performs this filtering function, is the reed. But also milfoil, calamus, Cyprus grass, or fir fronds are suitable for this purpose.

Plant baskets can prevent their plant helpers from spreading too extensively.

Last but not least, keep an eye on the nutrient content of the plant substrate you use. Make sure to use a low-nutrient product such as unique pond soil.

What Else Can Help With Pond Maintenance?

Carry Out Water Balancing/Supply Fresh Water to the Pond

Often it helps to perform a water balance in your pond. This is done by adding fresh water. Especially on hot summer days, this is extremely important as there is naturally more significant water loss due to the sun and heat. This helps to reduce the nutrient content in the water. The best water to use here is rainwater or tap water.

Do Not Neglect the Shore Area of the Pond

Often forgotten is also the shore area of the pond. If this is maintained and the plants in the immediate area are cut back, not as much organic material can get into your pond. Also to be cleaned and maintained are any walkways, pond entrances, and the like.

Possible Immediate Measures for Algae Control

If continuous pond care and all possible precautionary measures are taken, increased algae formation occurs in your pond, and special algaecides can help you. These are algaecides which either act by direct contact or by preventing the photosynthesis of the algae.

Here you should make sure to use only biologically safe products. There are especially such preparations that make use of the so-called sunglasses effect. Here the pond is colored almost invisibly amber. It shields the algae from the vital UV radiation of the sun.


I hope our guide could help you with essential questions about pond care. If you include the points mentioned above in your pond care and carry them out regularly, nothing will stand in the way of your well-kept dream pond. We wish you crystal clear water at all times and much joy with your pond.

Florian Egert

I am Florian Egert, the owner of I live with my wife and two children in Germany in a small village in the countryside.

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