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All you need to know about liners and on-site lining·

A choice may be self-evident!

If you are planning an overflow pool, an indoor pool, choose a on-site lining that will be welded directly into your pool.

In any other configuration, you are free to choose between a liner or a on-site lining. More flexible than the membrane, your liner will be made directly in our French manufacturing workshops, to the exact measurements of your pool and will be installed by your pool specialist.

How to choose your colour?

Colours that make a difference!

Colour is what you notice at first glance and choosing a liner is all about giving your pool a style. Contemporary or classic, deep or pastel, DEL colours allow you to perfectly match your pool with its surroundings and the style of your home.

The colours of the liners change once the pool is in water: go to our gallery to see how each colour looks in water!

How to maintain and protect your liner?


During the season, it is recommended to clean your liner once a week.

After emptying the skimmer and pump pre-filter baskets, clean the water line with a suitable, non-abrasive, solvent-free product, then sweep the walls and bottom of the pool. Finally, backwash the filter to prevent it from clogging. Cleaning the water line is important to get rid of lime deposits, grease (e.g. sun cream) and even micro-algae.

You can complete your cleaning with a robot cleaner, whose capacities will be adapted to your pool and its dimensions.

It is also advisable to renew one third of the pool water every year to avoid isocyanuric acid saturation and to replace the filter mass at least every 5 years (or according to the recommendations of each filtration equipment)


You can winterise your pool when the water temperature is below 10°C.

Opt for a winter cover to avoid the deposit of dead leaves at the bottom of the pool. If not, clean the pool frequently to prevent dirt and plants from staining the liner.

Maintain your normal water treatment or use a special winterization treatment.

To prevent frost damage to your pool or its filtration system, it is recommended to use an anti-freeze device (gizzmo) or to lower the water level. Do not touch the ice formations, as they could cut the liner.

Water treatment and balance

The maintenance of the pool and its water is very important to improve the life of the liner. Poor water balance can lead to problems with stains and wrinkles on liners. The capacity of the pump and its filter should allow for a filtration of the water for 4 to 6 consecutive hours. To find out the filtration time you can apply the following formula:

Filtration time = water temperature / 2

It is imperative to run your pump daily, especially in hot weather.

The water temperature should ideally not exceed 28°C, however, some of our liners are suitable for temperatures up to 33°C.

The PH of the water must be respected:

  • PH between 7 and 7.4
  • TH between 8 and 25°F
  • TAC between 8 and 12°F

Water maintenance must be done with special pool products. Several solutions are possible:

  • Inorganic chlorine, whose the level must be maintained between 0.7 and 1.2 mg/l. It is advisable to couple it with a stabiliser to guarantee its effectiveness.
  • The stabiliser or isocyanuric acid which must not exceed 70 mg/l.
  • Bromine should not exceed 2 mg/l.
  • PHMB is a disinfectant that has been banned since 2008 and should no longer be used.

DEL recommends the Chemoform brand products, to be found at your swimming pool specialist!

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