How a Natural Swimming Pool Works

The Kmobateva Operating Concept – Natural Swimming Pools

A natural swimming pool is a man-made, carefully engineered body of water with an ecological character, designed to maintain high water quality without the use of chemical disinfectants.

The processes that take place in a natural pool mimic natural aquatic systems: a delicate balance between oxygen, organic matter, and microorganisms. Unlike a lake or a stream, however, a human-made ecological pool must meet clear “domestication” requirements—maintaining a constant water level, clear water, and stable quality throughout the entire year.

To meet these requirements, a natural swimming pool typically includes several integrated systems:

• Water level compensation system – maintains a consistent water height

• Hydraulic circulation system – creates controlled water movement

• Filtration system – maintains water clarity

• Nitrate conversion system – reduces the buildup of ammonia and harmful byproducts

Ecology in a Nutshell

Biomass is the total weight of organic matter present in the water.

This includes:

• Fish and amphibious organisms

• Decomposing aquatic plants

• Organic material entering from the environment, such as leaves, flowers, pollen, dust, bird droppings, and more

All of this organic matter breaks down in the water and produces ammonia. Naturally occurring nitrifying bacteria then convert the ammonia through a biological process into nitrite and subsequently into nitrate.

While ammonia and nitrite are highly toxic even at low concentrations, nitrate is far less harmful and is readily absorbed by aquatic plants.

This, in short, is the core of the biological conversion process commonly known as the nitrogen cycle.

A Fundamental Condition: Balance

For the biological conversion process to function properly, one fundamental condition must be met:

The amount of dissolved oxygen in the water must exceed the amount of biomass in the system.

When biomass outweighs the available oxygen:

• The conversion process becomes incomplete

• Algae proliferate rapidly

• Biomass increases even further

• The water gradually turns into a green, turbid mass

To prevent this imbalance, efficient oxygenation of the water is essential.

Water absorbs oxygen primarily at the surface. Therefore, circulating water from the upper layers down into the deeper parts of the pool using pumps helps distribute oxygen effectively throughout the entire water volume.

Other oxygenation methods—such as waterfalls, fountains, or air bubbling—also exist, but they are generally less energy-efficient and require greater energy input to achieve the same level of oxygenation.

Water temperature also plays a critical role: the warmer the water, the less oxygen it can hold. As a result, higher water movement is required in warm conditions to maintain stability.

The North European Design Approach - Cold Climate Regions

In North Europe, a common natural pool design approach relies heavily on regeneration zones (planted wet areas), which often account for about 50% of the total pool area.

In other words, the ratio between the swimming area and the planted regeneration zones is approximately 1:1.

Water is drawn from the center bottom of the swimming area, passes through basic mechanical filtration, and is then directed into the bottom of the regeneration zones for further biological treatment.

In the North European climate:

• Summers are relatively wet

• The air is comparatively clean

• Environmental organic input is relatively low

• Water temperatures are cooler and oxygen levels are higher

Under these conditions, environmental factors place less strain on the system, as organic loads are lower and dissolved oxygen levels are naturally higher, allowing this approach to operate without immediately reaching instability.

Why This Works Less Effectively in Hot-Climate Regions

In hot-climate regions, the same North European approach tends to be less efficient due to significant climatic differences.

In hot-climate regions:

• Rainfall amounts and frequency are low

• The air contains high levels of dust, pollen, and pollution

• During peak summer, environmental biomass input may be up to five times higher than the biomass generated within the pool itself

• Water temperatures are high, resulting in lower dissolved oxygen levels

The accumulated organic matter breaks down rapidly, producing large amounts of ammonia. Oxygen deficiency accelerates this process, potentially leading to a gradual collapse of the biological conversion system.

Over a period of two to three years, the pool may deteriorate: green water, algae blooms, and eventually fermentation and unpleasant odors.

So, How Can Clear Water Be Maintained All Year Round?

The Kmobateva Operating Concept for Warm Climates

Natural swimming pools can and should be successfully implemented in warm climates as well, achieving levels of clarity, reliability, and hygiene comparable to the finest North European pools.

And all this:

• Without algae

• Without chlorine or chemical disinfectants

• With maintenance requirements lower than those of saltwater or chlorinated pools

The Kmobateva approach for warm climates is based on the integration of four complementary principles:

1. Highly Efficient Mechanical Filtration

Removing most organic material from the pool itself—rather than transferring it into planted regeneration zones. Water leaving the filters contains mainly dissolved nitrates and extremely fine particles.

2. Advanced Biological Conversion

Treating dissolved substances and remaining fine particles using a dedicated biological converter.

3. UV System for Pathogen Neutralization

Similar to systems used in drinking water treatment—neutralizing pathogenic bacteria that may survive the biological process.

4. Optimized Water Circulation

Creating maximum oxygen absorption throughout all layers of the pool.

The combination of these four elements produces a stable oxygen-to-biomass balance that, in warm climates, significantly outperforms the traditional North European approach.

The result: clear, clean, high-quality water throughout the year—regardless of environmental load.

Why the Kmobateva System Is Also Advantageous in Cold-Climate Regions

It is important to note that the Kmobateva system is not limited to warm climates. In fact, it offers clear and practical advantages in North European and other cold-climate regions as well.

By relying on high-efficiency mechanical filtration, controlled biological conversion, and optimized hydraulics, rather than large planted regeneration zones, the system requires significantly less space and substantially lower ongoing maintenance.

Eliminating extensive plant zones reduces seasonal plant management, sediment accumulation, and long-term organic buildup—factors that often create maintenance challenges even in cold climates.

As a result, the Kmobateva approach provides a more compact, predictable, and low-maintenance solution, while maintaining consistently high water quality—independent of climate conditions.

Conclusion

A successful natural swimming pool relies on controlled design. By managing organic loads, oxygen availability, and biological processes, the Kmobateva system delivers clear, stable water with less space and maintenance—performing reliably across both warm and cold climates.