swimming pool construction London


24 February 2017
Filter choices for your pool

For healthy swimming, it’s vital that the pool water is always clean and properly filtered, this will not only prevent any potential waterborne diseases taking hold, it will ensure that the volume and the cost of chemical treatments for your pool are well managed. There are different types of filters from which to choose and we look at three – two long-standing options and one relatively recent development; all achieve a high level of water purity.

Sand Filter Media
This was one of the first ways of filtering water and is still used today, though typically it is now quartz or crystalline silica that is used to trap debris from the water and backwash it to the waste collection. Originally used in one form or another by the Romans, sand filters are very easy to install and set-up and is the least expensive choice. The only downside of using a sand filter is that it will require regular backwashing of the pool water and this process leads to a loss of heated water.

Activated Filter Media®
A relatively new media is Activated Filter Media, which is made from a particular type of green glass that filters so much finer than sand or glass sand, producing crystal clear, odourless pool water.  AFM is superior because it filters at least 30% more organic substances and is bio-resistant and self-sterilising which means no biofilm is formed in the filter bed.  This feature makes the pool system healthier, ecological and more economical to run.

Glass may seem like an unusual media, but rest assured, AFM is made from the finest materials and manufactured to the highest safety standards.  No glass splinters are allowed to be present in the filter material.  The raw material used to produce AFM contains only pure green glass, which has the necessary metal oxides to make it self-sterilising.  The raw material is broken into the optimal grain size and shape as the correct shape is crucial for the outstanding hydraulic characteristics of AFM.

Cartridge filters
The main difference between cartridge filters and other kinds of filter media options is that most of them don’t have a filter media bed meaning that they do not need to be backwashed.  As a result, this saves on water, energy and space since they do not require a backwash line which takes up space and requires extra power. The flip side to using cartridge filters in your pool is that they must be removed and cleaned manually (ideally with a hose from the top down), which takes time, though likely isn’t necessary more than once per season. To ensure that your cartridge filter has a long life, they should be cleaned with the correct chemicals for ideal cleanliness – if not well maintained they can have a limited lifespan.

Want more help?
As you’re probably not an expert in pool filters, before making a purchasing decision, speak with a qualified and experienced pool servicing engineer who will be able to talk you through the options and help you decide what’s best for your pool given the size and bather load.

At London Swimming Pool Company we specialise in swimming pool design, construction,  refurbishment and maintenance, so if you need advice contact us for an initial discussion – there’s no substitute for expert advice.

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