By recirculating the same water, it eliminates the need to constantly drain the pool, saving time and money. Pool filter systems remove dirt, debris, and other contaminants that accumulate over time. This ensures the water remains clean and safe to swim in.
The Pool Filter System: The Backbone Of The Pool
The pool pump helps to move the water through the pipes and the pool filter removes any unwanted particles and contaminants, providing safe and clean water for use. The pump and filter work together to ensure the water is properly circulated and clean. This helps to prevent the growth of bacteria and algae, and maintains the clarity of the pool water. Although additional disinfection or heating equipment can be added, these devices are not necessary for the pool to function properly.
Proper sizing of the pool filter system is crucial to ensure the pool’s optimal performance. It should be based on:
- The volume of water in the pool,
- the use of the pool (private or publlic)
- the budget,
- whether an overflow is present or not.

Knowing more about pool filtration is essential, as it is the key to unlocking the 80% of water maintenance that is done through the filtering mass. The remaining 20% is handled by maintenance products.
What's The Process For Filtering Pool Water?
The pool piping layout brings the water from the pool to the technical room, where the pool filter system is installed. Through the skimmers and bottom drain, water is drawn from the pool. After the water is filtered and treated, it is returned to the pool via the return inlets, providing a clean and healthy environment for swimming.
The pump draws water from the pool and pushes it through the filter. The filter media captures particles as small as one micron, ensuring crystal clear water free of contaminants. This media is typically sand, diatomaceous earth, or cartridge filters. Each filter has its advantages and disadvantages in terms of how efficiently it filters out impurities from the water.
Morana's advice 👇
Assess your pool’s needs
When selecting a filtration system, it is important to take into consideration the size of the pool, the volume of water, the type of use (residential, community, or commercial), and the frequency of use. A filtration system should be selected based on these factors.
Take a look at the filtration system’s efficiency and maintenance
The various types of filtration systems (sand, cartridges, and diatomaceous earth) have their advantages and disadvantages in terms of filtration efficiency and ease of maintenance. Determine how much maintenance you are willing to undertake and how clean you wish your water to be.
Get the best design for your pool filtration system.
Which Pool Filter System Is Right For You?
The type of filtration system used in a swimming pool will determine how well the water is filtered and how often it needs to be changed. Different types of filtration systems provide varying levels of filtration fineness, and it is important to understand these differences to ensure that the swimming pool is properly filtered and maintained.
Cartridge filter
Because it’s easy to install and uninstall, it’s mostly used in small above-ground pools. Pool cartridge filters use a pleated filter cartridge to capture dirt and debris from the water. The cartridge is made of paper or polyester that is designed to trap small particles and allow the water to flow more freely. The cartridge must be replaced regularly to maintain the filter’s efficiency.
Cartridge filter benefits:
- Cost-effective.
- Maintenance is low water, just soak and rinse.
- Easy to put in and take out.
- Compact footprint.
Cartridge filters drawbacks :
- Cleaning frequency: about twice a week during the season.
- Cost per use: cartridges must be changed regularly.
Pool sand filter
This system is known for its reliability, efficiency and easy maintenance, making it a preferred choice for pool owners. It is suitable for all pool sizes, whether in-ground or above ground. It can use different filtering media depending on the fineness required. The backwash reverses the flow of the filtration system, allowing the water to flush out any accumulated dirt and debris from the filter media.
The pros of a sand filter :
- Long lifespan.
- Easy to maintain.
- Multiway valve on the tank makes backwash easy.
- Suitable for all types of water, including very hard ones.
The cons of a sand filter :
- Water consumption is high if you use sand because it needs frequent backwashing.
- Important bulkiness.
Sand as filtering media
The pool filter is filled with silica (sand and gravel) when it is first put into service. Silica acts as a trapping agent to catch and hold dirt and debris that passes through it. The filter is then cleaned periodically to remove trapped particles. Cleaning may involve backwashing or chemical cleaning. The filter is then ready to start the filtration cycle again. To ensure optimal filtration, grain sizes (granulometry) are controlled.
In limestone waters, the grain size can increase and form blockages, making the filter less effective. Additionally, the bacteria in the sand create a sticky film called biofilm, which also reduces filtration quality. As a result, the overall filtration quality (typically between 30 and 50 microns) can decrease significantly, making it difficult to achieve the desired water quality.
What's better than sand?
Sand is a tried and true filter material, but modern pool owners can explore various other options to ensure clear, clean water
Zeolite: Due to its three-fold higher cost than sand, this microporous volcanic rock is not widely used. Despite its higher cost, zeolite has several advantages that make it worth considering: improved filtration fineness (about 5 microns), a longer lifespan (over 10 years), and better pH stabilization.
- Crushed glass is a more cost-effective and environmentally friendly alternative to zeolite. The crushed glass can filter out small particles, like algae, bacteria, and dirt, while also maintaining the water’s pH balance. Additionally, the crushed glass is made of recycled and polished glass granules, making it a much more sustainable option than zeolite.
- The textile filter media known as Pureflow is composed of thousands of tiny fibers. This media is designed to capture and hold dirt particles down to two microns in size, which is much smaller than the particles that can be trapped by traditional zeolite media. Additionally, it has a very high dirt holding capacity , which means it can filter the same amount of water with less media, leading to less backwashing and lower maintenance costs.
Diatomaceous Earth (DE) Pool Filter System
Diatoms are fossilized micro-algae with a filtering capacity of approximately 1 to 3 microns. The diatoms create a thin layer on filtering membranes placed in a tank similar to a sand filter. This layer must be renewed periodically to keep it efficient. The DE Filter is effective at trapping particles as small as 1 to 3 microns, which helps to make sure that the water is clean and safe for swimming.
The advantages of the diatomaceous earth filter
- Filtration fineness unmatched.
- Backwashing reduced to once every two months.
- Filter membranes and the tank are washed with jets, so it’s water-saving.
- Reducing chemical use.
The disadvantages of a DE filter :
- Almost twice as expensive as sand filtration.
- Not suitable for limestone water.
- Certain chemicals, like PHMB, algaecides, and flocculants, are incompatible.
How To Improve The Performance Of Your Pool Filter System?
While building a swimming pool, the choice of a pool filter system is not the only factor to consider. Filters of any type will not perform as expected without the right pump and a well-designed piping layout.
To ensure successful operation, the piping layout should be carefully considered and implemented. Additionally, the placement of valves, strainers, and other components will affect the system’s efficiency and should be considered in the design process. The hydraulic system must be designed to ensure it runs as efficiently as possible and that all chemicals and treatments are properly mixed.