Swimming Pool Filters
The swimming pool filter is an important part of the whole swimming pool system, it removes the particles of dirt, skin etc from the water. Without the filter, the pool water would be very cloudy, even with the correct use of chemicals.
There are different types of pool filters depending on the application. Normally domestic inground pools use a high speed sand filter. Above ground pools and temporary pools use a paper or cloth cartridge filter.
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On the left we have a cartridge type filter, complete with its pump. The filter can be cleaned by removing it and washing away the dirt. Once the filter becomes too dirty or its performance is impaired a new cartridge is installed. This type of filter is often used on Jacuzzis and Spas. |
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The high speed sand filter. The red tank is filled about 2/3rds full of washed and graded sand (or other filter media). The sand traps the particles of dirt as the water passes through it. When the filter is dirty, it is cleaned by reversing the flow of water through it and washing the dirt away. Every couple of seasons, the sand will need replenishing and every 4 to 5 years it will need to be changed. |
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| The 6 way or Multiport valve controls the flow of water through the filter, for backwashing etc.. | Washed and graded filter sand. This is a type of sand, chosen because of its size and grade. | The collectors in the base of the pool, stop the sand leaving the filter. They should be replaced when the sand is changed. |
A very useful video showing the operation and functions of the 6 way valve.
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A typical domestic swimming pool pump and filter group. |
Diatomaceous Earth Filters
This is a kind of filter that uses a medium that is made up from the fossilized skeletons of microscopic Diatoms. These are like microscopic sponges that filter out particles as small as 3 microns. The smaller the particles that can be filtered out, the better the water quality. These types of filters have to be topped up after each backwash making them more maintenance intensive. These filters are not common place in Europe, but if needed they are available, the filter medium is sold by Astral, branded as "CELITE".
