- are tanks that hold 3 or more cylindrical cartridges, similar to the cartridges in an automotive oil or air filter, made from a material such as polyester, which trap and hold particles down to about 5-10 microns

They are usually priced between Sand-filters and DE Filters

Cartridge filters require very little maintenance.  You can sometimes get away with hosing the cartridges off 3 or 4 times during the swimming season.  If this is insufficient you may need to soak the cartridges in a cleaning solution

At worst you may need to replace the cartridges, which are usually relatively, but occasionally can be VERY expensive.  When choosing a cartridge filter for your pool first discover the price and availability of replacement cartridges

wikiHow has some good advice on cleaning cartridges, see their advice here

At the Piscinas Exhibition in Barcelona in 2011 we saw a cartridge filter that was huge.  It is designed to be cleaned just once per year and as soon as I can track them down I'll add their information to this page

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*We only offer Quotations: - a fixed, agreed price that cannot, and will not, be increased. We do not give 'estimates', as an estimate offers the client no guarantee of final price

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DE filters are the most efficient (or rather were the most efficient before Zeolite became available), and dearest, type of filter and they will trap dirt particles down to 3-5 microns

                 Hayward D.E. 2420 Pool Filter

However, a sand-filter containing Zeolite, or a standard sand-filter media, such as Silex or crushed glass, used in combination with Jolly Gel, will filter to the same standards as a DE filter

• Diatomaceous Earth is a fine powder made from billions of fossilised plankton skeletons

• DE powder is so fine that it is a skin irritant and great care must be taken not to breath the dust as it is considered (by some Health Authorities) to be a carcinogenic

• The inside of a DE filter holds a number of fine grids coated with DE powder

• It works exceptionally well to catch and hold dirt

• Maintenance of DE filters can be demanding, though: - 

• Most types require periodic back-washing and this is not always sufficient to get them thoroughly clean

• You may need to remove the grids periodically, discard the used DE powder and thoroughly clean your DE filter

• This can be problematic because some towns (in the USA, notably) classify spent DE powder as toxic waste, so it cannot be dumped

We supply all plant and equipment featured on this website. All our work is Guaranteed; Parts and Labour

For free and unbiased advice, a site visit or no-obligation Quotation*, please make initial enquiries by email. Tell us a little about your pool problem and include a daytime phone number. Thanks, we look forward to meeting you soon

Note: - Please contact our recommended pool professionals for supply and installation of all pool-related services: - 

Andalusia and the Costa del Sol - Pool Safety Spain

Nerja area - This email address is being protected from spambots. You need JavaScript enabled to view it.

*We only offer Quotations: - a fixed, agreed price that cannot, and will not, be increased. We do not give 'estimates', as an estimate offers the client no guarantee of final price

Share this website with other Pool Owners and Users,  encourage them to read about Pool Safety, learn CPR and help them to save lives, time and money. Please help us to make every pool a safer place - by sharing this information we can cut the number of pool accidents and deaths.  Please also see our Facebook page

Ken Walker - MyPoolGuru©

- keeping the water clean

Pool water is filtered when it is pumped through a bed of sand in the sand-filter

Beach, river or building sand is hopelessly inefficient in a sand filter as it is ‘round’ in form from being rolled in water, which removes the sharp edges

                                                             Sand Filter Layout  

Sand-filter sand, called Silex, is crushed from silicate rock, producing sand grains with very sharp edges

The sharp edges and smooth faces of these tightly-packed cubes leave microscopic channels for the water to pass through and it is the size of these channels that determines the size of particle that the sand-filter can trap and hold

New Silex is quite efficient as a filter medium but, over time, backwashing damage the media by bashing it around when the filter bed is 'fluidised'; chipping microscopic flakes off.

These microscopic particles are much too small to be caught in a filet, and too small to sink to the floor of the pool. They are constantly re-circulated through the filter, eroding tiny pits in the faces of the grains and smoothing the sharp edges; therefore efficiency will fall off.

The filter will become unable to trap the smallest particles with the result that the pool water will become cloudy.

Cloudy water can be corrected with flocculant but, with an inefficient filter, the problem will gradually return.

Jolly Gel will catch the microscopic particles by contact and double the filter media life.

The best course of action is to change the sand in the filter and to fit Zeoclere-30 as an alternative filter media. When Zeoclere-30 is used in conjunction with Jolly Gel the filter media will last for 10+ years.

Changing the filter media is an unpleasant job at best; usually involving a couple of sweaty hours crouched uncomfortably over a filter filled with what can best be described as gritty, sterile liquid sewage.

If you’d like to do this job yourself you’ll find instructions here.

We supply all plant and equipment featured on this website. All our work is Guaranteed; Parts and Labour

For free and unbiased advice, a site visit or no-obligation Quotation*, please make initial enquiries by email. Tell us a little about your pool problem and include a daytime phone number. Thanks, we look forward to meeting you soon

Note: - Please contact our recommended pool professionals for supply and installation of all pool-related services: - 

Andalusia and the Costa del Sol - Pool Safety Spain

Nerja area - This email address is being protected from spambots. You need JavaScript enabled to view it.

*We only offer Quotations: - a fixed, agreed price that cannot, and will not, be increased. We do not give 'estimates', as an estimate offers the client no guarantee of final price

Share this website with other Pool Owners and Users,  encourage them to read about Pool Safety, learn CPR and help them to save lives, time and money. Please help us to make every pool a safer place - by sharing this information we can cut the number of pool accidents and deaths.  Please also see our Facebook page

Ken Walker - MyPoolGuru©