To find out a bit more about pool filtration, we sat down with Hayward Victoria District Technical Manager Andrew Waldron to discuss why this technology is so good it doesn’t need changing and what considerations you need to make before choosing the right filter for you.
How has filtration changed over the years
Development of pool filtration has been slow moving for a number of years, the two most common types of filtration are media filters and cartridge filters. These have remained relatively unchanged for a long time which is testament to the performance of these methods of filtration. They do a great job, are reliable, simple to use and relatively low cost. Rather than trying to re-invent the wheel, pool equipment manufacturers have preferred to concentrate resources on other areas of the pool equipment pad, prioritising the development of equipment that can make a bigger difference to the pool ownership experience.
For manufactures, most developments in filtration have largely been focused on improving reliability, ease of install and cost of equipment, rather than innovations in the method of filtration.
What’s the importance of pairing the right pump with the right filter — and why?
Pairing the right pump with the right filter is very important for achieving the correct turnover rate for your pool. The turnover rate is the number of hours it takes for the total volume of the pool to pass through the filtration system. Ideally your pool filtration system should have the ability to turn the pool water over completely 1 ½ – 2 times per day.
Therefore, it is essential that you size your pump and filter to allow for this. If you have an undersized pump, it won’t have the power required to circulate the water through the filtration system and achieve the required turnover rate. However, if you have a pump that is too powerful, it can put too much pressure on the equipment, potentially causing the filter to function incorrectly or even break.
What’s the difference between Cartridge and Media filters?
Within the residential pool market there are two main methods of filtration, a cartridge filter or a media filter.
So, what’s the difference?
Media Filters:
Media filters use a bed of a material made up of fine particles (generally sand or glass) to catch debris as the pool water is pumped through it.
Cartridge filters:
Cartridge filters use a finely weaved polyester material to catch debris that is pumped through it, like a covid style face mask. The material is generally pleated to allow for a larger surface area and a higher flow rate.
So, which should I choose?
Whichever method you chose, each has their pros and cons.
When it comes to actual filtration performance, to the naked eye there is very little to tell them apart, whether using a media filter or a cartridge filter your pool will look clear and clean. But if you want to get technical, Media filters will filter down to around 20 microns, but cartridge filters can go even finer at under 10 microns.
Whether you go for a cartridge or a media filter, there is regular maintenance required to keep a pool filtration system operating at peak performance. The method of filtration you choose may depend on the regularity of maintenance you’re willing to take on and the level of work required during maintenance.
The maintenance of a cartridge filter requires the user to open the body of the unit, remove the cartridges and clean them with a hose. This can be a messy experience and if the pool is in an area of high debris, it can require this to be done fairly regularly to maintain performance.
A media filter on the other hand generally requires less frequent maintenance, however when it is required it can be slightly more work. Backwashing a media filter is a relatively straightforward process, but it does lower the water level of your pool and some of the chemicals in the pool will be lost, the pool may also require rebalancing when it is topped back up. In order to backwash, access to a sewer is also required as it is illegal to dump the waste water into storm water drains. This can have an effect on the type of filter that can be chosen for a site. If the site doesn’t have access to a storm water drain, then a cartridge filter may be the only option available.
Another consideration you may have are the long-term cost associated of the filter. Generally, in this debate media filters usually win. It is generally thought that a media change will occur less frequently than the need to replace filter cartridges.
What is the role of regular filter servicing?
Regular servicing of a pool filter plays an important role in the performance of a pool. The key role of servicing is to clean the filter. If this is not carried out on a regular basis, filters can clog and restrict the flow of water through the filtration system. This will cause the pump to work harder and use more energy, it will put increased pressure on the filter and other equipment on the pool and it will reduce the filtration performance. Restricting the flow of the filtration system will prevent the pool turning over the 1 ½ to 2 times per day that is required, meaning that the water clarity may be reduced and debris may remain in the pool.
What’s one thing that users often don’t get told about maintaining their filter?
It is very important to ensure that the pressure gauge on a filter is working correctly to make it easy to recognise when a filter needs to be cleaned, this is often overlooked by pool owners. It is far easier and cheaper to stay on top of filter maintenance, than to pay it no attention and suffer high energy bills and servicing costs when an issue becomes apparent. Pool owners should talk to their local Pool Professional when they get their equipment serviced and find out what pressure the gauge needs to be reading to indicate that it needs to be cleaned.
Hayward always recommend that you speak to your local Pool Professional. Every pool is different and what may be the right solution for one pool may be wrong for another. To find your local Pool Professional, simply hop on to the Hayward Dealer Locator