Many people moving to Languedoc inherit a pool, and are concerned about costs and maintenance. Small sized pools need little, but regular maintenance to keep them sparkling. This is achieved mainly by cleaning the bottom with a "vacuum cleaner" - a brush using water pumped through the filter.
The pool above (a neighbours) had been abandoned for 2 weeks in July in the midst of a divorce dispute.
Pools can be above ground, in the ground or both, if on sloping ground.
True above ground pools are normally made from a metal framework, supporting a plastic liner. Some of the smaller ones are pneumatic. These pools heat up and cool down faster than in ground pools. They are inexpensive to buy in the larger garden centres and Do it Yourself shops.
In ground pools are either formed from concrete and paint, concrete and or steel with plastic liner, plaster and tiles, or use a fibreglass shell.
Water temperature depends on hours of sunshine, air temperature, ground temperature (in ground), use of a cover, wind (evaporation = cooling) and any heating system used.
All use several different systems of filtration. Skimmers collect floating debris, leaves etc, and pre pump filters collect smaller impurities. Then, normally, the water is circulated through a sand filter, which is easily cleaned by reversing the flow periodically and pumping the dirt to waste.
All use a system to disinfect the water. The most common system is to use chlorine by means of tablets. Note that typical chlorine levels for private pools are much lower than those for public pools. The water is easily tested to ensure it is safe and clean.
Other systems use bromine, oxygen, ozone, ultra violet light, Cl generated from salt water etc.
Bromine is claimed to be less harmful to sensitive eyes, but is more expensive than Chlorine.
Salt water pools use a very weak salt solution (likened to tears). The water passes through an electrolysis unit that releases chlorine into the water. Salt has to be added as it is used in the production of chlorine. They are increasingly popular.
Environmental issues are beginning to impact choice of system in some areas.
Maintaining a pool of 50 m3 (50 tons) or 8.5m X 4m X 1.5m takes about 15 minutes every two days, providing it is maintained regularly. In addition a more thorough monthly clean takes about 2 hours. Expect about 3 hours at the start of the year to clear the winters accumulation of dirt.
Once "out of control" (= algae starts to grow) it can take much longer !
Pools are normally covered from November to March in Languedoc and during this period little or no maintenance is needed. However some owners maintain the pool year round. Note that in ground pools are kept full of water year round. If emptied there is a risk that the ground water table will float the empty pool upwards.
The easiest pools to maintain are small (up to 50m3) pools with a fibreglass shell. The shell is inert, which helps minimise chemical use.
Typical running costs of a 50m3 pool are -
- filtration (3 - 15 hrs per day according to temperature) costs around Euro 15 per month for electricity in summer.
- Chemicals are cheap. 25 "all in one" chlorine based tablets of 200gm cost around Euro 25, and a tablet lasts between 5 and 10 days according to temperature. Other chemicals are used occasionally in small quantities at insignificant cost.
- During one year, expect to use the same volume as the pool again for bottom cleaning, replacing evaporation losses and filter cleaning. Typically, domestic water costs up to Euro 2.5 per m3.
- The costs are proportional for larger pools based on the capacity in m3.
Maintenance can be reduced by using a robot. There are 2 varieties -
- The cheapest at around Euro 150 is driven by water pressure and is efficient where the pool has rounded edges (otherwise it tends to stick in the corners).
- For an investment of about Euro 1800 you can buy an electrically powered robot, with a tanklike drive. They are very efficient. Many can be preprogrammed with a remote control.
A South facing pool will achieve around 30 C in July / August without any external heating. External heating is expensive, but is used to extend the season. Solar heating and under terrace heat exchangers are effective, and cheaper to run.
The latest generation of heat pumps are relatively economic. They can generate up to 3.5kw of heat from 1 kw of electricity. Domotechnologie have technical details of the various solutions on their website (in French).
Thought needs to be given to new pool installation. The pool should be, exposed to the sun, sheltered from prevailing winds and away from plants that drop leaves. Water flow to the skimmers should be with the prevailing wind. There are safety regulations that need to be considered.
Buy a pool maintenance manual through Amazon for peace of mind. I bought The Ultimate Pool Maintenance Manual by Terry Tamminen. Amazon links are from US and from UK.