Pool Guide

Why is the filtration system so important?

The filtration system represents about 80% of the maintenance of a swimming pool. It removes:
- Leaves, insects and floating debris.
- Fine particles suspended in the water.
- Bacteria and micro-organisms that can cloud the water.
Without effective filtration, the water quickly becomes cloudy, promoting the growth of algae and requiring excessive consumption of chemicals.

The different types of swimming pool filters

1. The sand filter

The sand filter is the most common system in private swimming pools. It works by circulating the water through a bed of sand that retains impurities.
Advantages:
- Easy maintenance thanks to backwashing.
- Long lifespan (10 to 15 years).
- Suitable for large swimming pools.
- Relatively affordable.
Disadvantages:
- Less effective at filtering very fine particles (20 to 50 microns).
- Consumes a lot of water during backwashing.
- Sand needs to be replaced every 4 to 5 years.

2. The cartridge filter

This type of filter uses a synthetic fabric cartridge that traps impurities and offers a higher level of filtration than sand.
Advantages:
- Finer filtration (10 to 20 microns).
- Low water consumption (no backwashing).
- Compact size, ideal for small pools.
- Quick and easy maintenance (rinsing with a water jet).
Disadvantages:
- Less suitable for large swimming pools.
- Cartridge to be replaced every 2 to 3 years.
- More frequent cleaning than a sand filter.

3. The diatomaceous earth filter is the most efficient of the three, offering extremely fine filtration thanks to a natural mineral powder. Advantages: - Ultra-fine filtration (2 to 5 microns). - More crystalline water than other systems. - Reduction in the use of chemical products.
Disadvantages:
- More demanding maintenance (more frequent cleaning).
- Higher initial cost.
- Diatoms need to be replaced after each backwash.

How do I choose the right filter for my pool?

The choice of filter depends on several criteria:

1. The size of the pool

- For large pools (+50 m³), a sand filter is recommended for its high flow rate.
- For medium-sized pools (20-50 m³), a cartridge filter can be a good alternative.
- For consistently clear water and smaller pools, a diatomaceous earth filter offers the best results.

2. Frequency of use

- A swimming pool used daily by several bathers requires a high-performance filter (diatom or cartridge).
- An occasionally used pool can make do with a sand filter.

3. Available space

- The cartridge filter takes up little space and is suitable for small technical rooms.
- The sand and diatomaceous earth filters require more space.

Filter maintenance and lifespan

1. Maintenance of the sand filter

- Backwashing every 2 to 3 weeks.
- Sand replacement every 4 to 5 years.
- Regular checking of the pressure gauge pressure.

2. Maintenance of the cartridge filter

- Rinse with a water jet once a week.
- Soak in a descaling solution once a month.
- Replace the cartridge every 2 to 3 years.

3. Maintenance of the diatomaceous earth filter

- Frequent backwashing to remove used diatomaceous earth.
- Addition of new diatomaceous earth after each cleaning.
- Checking the filter grids and replacing them if necessary.

What is the best choice in 2025?

The choice of filter depends on your priorities:
- If you are looking for an economical and robust system: The sand filter remains a safe bet.
- If you prefer fine filtration and simplified maintenance: The cartridge filter is a good option.
- If you want crystal-clear water with the best filtration: The diatomaceous earth filter is the most efficient.

Effective filtration for a healthy swimming pool

Investing in a good filtration system is the key to maintaining clean water and reducing maintenance costs. By choosing the right filter for your pool and maintaining it regularly, you can guarantee clear water all year round.
Whatever system you choose, a properly sized and maintained filtration system will ensure that your pool lasts a long time and that bathers are comfortable.