Natural Swimming Pools: What to Know About This Chlorine-Free Alternative

Few things are more refreshing than a plunge into your own personal swimming pool, but the harsh additives that control the pH, water hardness, and alkalinity can be irritating to swim in (not to mention maintain). 

If you're interested in a more low-maintenance alternative that doesn’t use chlorine or chemicals like algaecide or bromine, a natural swimming pool might be just the ticket. These pools, also known as living pools, mimic the bioactivity of natural ponds, eliminating the need for chemicals while still providing a clean swimming experience.

What Is a Natural Swimming Pool?

A natural swimming pool is a microcosm of the ecosystems found in natural ponds. Instead of relying on chemicals, they stay clean through the use of moving water and natural bioactive filtration systems. 

An adjacent body of water next to the main swimming pool—known as the regeneration zone—contains aquatic plants that naturally filter and oxygenate the water, promoting the growth of beneficial flora that help keep it clean.  

Yes, that means you won’t need chlorine tablets and you won’t have to add chemicals like algaecide, bromine, clarifier, and more. 

Natural Pools vs. Chlorine Pools

Unlike natural pools, chlorine pools use chemicals to keep the water clean. While both types of pools use filters and need to be cleaned, the chemicals used in chlorine pools are much harsher on the skin and eyes than their natural counterparts.

Natural Pool vs. Living Pool

While a natural pool uses a regeneration zone to help keep the pool clean, a living pool uses an underground biofilter and phosphate filter that absorb phosphates and promote the growth of good bacteria to maintain cleanliness. 

How Natural Pools Work

A natural pool isn’t the same crystal-clear turquoise color, but it still has the same level of safety and cleanliness as a traditional chlorinated swimming pool. Here’s what a natural swimming pool should have in order to work successfully.

Plants

Plants are an essential part of a natural swimming pool’s filtration system. They encourage the growth of flora that keep the water clean, just as they do in natural ponds. The plants are housed in the regeneration zone adjacent to the swimming pool. The use of liners ensures you won’t see any stray plants in your swimming area.

Shade

You should place your natural swimming pool in a shady location. Algae thrives in direct sunlight, so a sunny location could make the natural filtration system work much harder than it needs to. 

Gravel/Aggregate Materials

Gravel and other aggregate materials work as a filter in the regeneration zone. These also anchor down any rooted aquatic plants.

Water Pump

Natural swimming pools need a pump to cycle the water through the regeneration zone and throughout the swimming area. This constant movement also helps prevent the growth of algae, mold, bacteria, and other unwanted organic materials. It also naturally keeps frogs out of your pool, as well as other wildlife.

Aerator

Plants and other bioactive components of the pool need oxygen to stay healthy. While plants naturally oxygenate the water, an aerator maximizes the oxygen levels in the water. Underwater aerators connect to the pump and are a great investment to allow your ecosystem to thrive.

Liners

Natural swimming pools can look and feel surprisingly similar to traditional pools, despite the presence of plants and other organic materials. Liners prevent leaks and keep your feet free from soil and sediment. These also seal off the regeneration zone, preventing plants and other components from blending with the swimming area.

Natural Swimming Pool Pros and Cons

Natural pools are kinder to the environment than their chemical counterparts, plus the concept lends itself to a variety of beautiful, nature-inspired pool designs. They’re also more low-maintenance and won’t burn your eyes or ruin your blonde highlights. 

Still, they’re not for everyone. A higher upfront cost can be a big drawback for natural pools, as well as the extra space they need to accommodate their regeneration zone. 

Some people also can’t get past the murkier water of a natural pool—it’s not muddy by any means, but it’s not the same crystal-clear turquoise that many are accustomed to. It’s important to weigh your priorities when deciding whether a natural pool is right for you.

Natural Pool Benefits 

• Better for the environment: eliminates use of chlorine and other chemicals that can harm the environment

• Lower maintenance: requires little maintenance other than plant care and skimming physical materials

• Saves money over time: ends need to constantly repurchase pool chemicals

• More natural: Chemical-free water replicates swimming in a natural body of water

• Less irritating: Keeps water clean without use of irritating chemicals

Natural Pool Drawbacks 

• Higher upfront cost: may cost up to twice as much as regular pools to build

• Greater space requirements: can take up significantly more space due to the separate regeneration zone

• Water appearance: murkier appearance than chemically-treated water

• Less common: fewer swimming pool companies specialize in natural pools

Natural Pool Maintenance 

Traditional swimming pools have a laundry list of pH balancing, chlorine additions, and other fine-tuning tasks to ensure they stay clean. 

Natural pools, on the other hand, are largely self-sustaining and require very little maintenance aside from trimming and replacing plants where needed, and skimming away physical materials. You can even leave them alone and allow them to naturally freeze over during the winter, just like a natural pond.

Things to Consider When Installing a Natural Pool 

Natural pools are a marriage of tranquility and function. They’re an excellent solution for homeowners who don’t want to manage traditional pool chemicals or want a pool that blends seamlessly into the nature of their backyard —but they’re not right for every home. There are a few things you should consider before (literally) diving in. 

Budget

Natural swimming pools are a high-end amenity that come with a high-end price tag. They’re one of the least affordable types of pools on the market—right up there with inground gunite or concrete pools. You can purchase DIY kits that lower installation costs, but it’s difficult to install compared to a DIY above ground pool. Most homeowners need a pro.

Space

One of the biggest limitations homeowners face when installing a natural pool is space. This type of pool requires two separate bodies of water—one for swimming and one to house the regeneration zone. It’s not ideal for small yards, though you can play around with different pool shapes to find something that will best suit your property.

Climate

Unlike traditional inground pools, you won’t need to drain a natural pool during the winter. In fact, you can use it as a mini ice rink if it freezes completely (never skate on ice less than four inches thick). That said, you may also want to install a pool heating system—whether it’s a solar or a traditional pool heater. In a warm climate, this will allow you to use your pool year round.

Contractor Availability

It’s really important to install your natural swimming pool correctly. Otherwise, it won’t work the way it should and the water could make you sick. While it’s key to follow the steps of how to hire a pool contractor, not every pool contractor has experience with this type of pool even then. Make sure to hire someone who specializes in natural pool installation. Don’t know where to start? Check out some pool installers near you.

What Are the Best Plants for a Natural Swimming Pool?

Plants in the regeneration zone help keep the water healthy and oxygenated while aiding in water filtration. Emergent and underwater plants oxygenate the water and feed beneficial microorganisms. 

Floating plants such as water lilies provide additional oxygenating benefits while also giving shade to the microorganisms that help keep the pool clean. Here are some of the best pool plants.

Floating Plants

• Waterlilies

• Duckweed

• Mosquito fern

• Water hyacinth

• Water lettuce

Emergent Plants

• Sedge

• Cattail

• Arrowhead (duck potato)

• Pickerel weed

• Rush

Underwater Plants

• Hornwort

• Pondweed

• Waterweed

Are Natural Swimming Pools More Expensive Than Regular Pools?

The cost of natural swimming pools is almost always higher upfront than regular swimming pools. Traditional in-ground pools cost anywhere from $39,000 to $70,000, while the average natural pool typically goes for at least $60,000 to $70,000. 

However, as you won’t need to keep shelling out for chemicals, natural swimming pools cost less over time. You might also be able to shave off some of your budget if you time your pool purchase wisely during the off-seasons when sales are more likely.

Talk to swimming pool companies in your area to find one that specializes in the installation of natural pools. 

Can You DIY a Natural Swimming Pool? 

It’s possible to DIY a natural swimming pool, but it’s an advanced-level project that requires know-how on all the elements. A base understanding of natural ecosystems is essential to selecting your plant/regeneration zone setup. 

Along with that, there are a few physical setups that can be challenging or even hazardous for a beginner. You may want a local electrician to help you safely set up the water pump or a plumber near you to help run underground piping from the regeneration zone to the swimming area. 

Either way, as long as you do your research and outsource jobs when needed, your build should go swimmingly.

Mariel Loveland contributed to this piece.