A Closer Look at The Three Types of Pool Filters

By:Shane Dwight
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Swimming pool filters are systems that are installed as part of your pool to help clean and keep your water free from debris such as dirt, twigs and leaves as well as contaminants. Most people utilize water treatments like chlorine in conjunction with a filter, but it’s possible to operate yours with just a filter, depending on how safe the water is in your region.

Apart from removing debris, filters ideally keep the water flowing, thus reducing the risk of parasites and insects from breeding in the pool. They also prevent algae from growing on your water.

There are three common types of filters out there which we shall discuss in this read.

Cartridge Filter

This is a big tank which features a cartridge filter inside that traps particles that are as small as 10 microns. These filters don’t need backwashing are simple to remove. When it comes to cleaning, you can remove the cartridge and then spray it with water using a hose. Keep in mind that these filters need to be replaced after several years, depending on the brand plus use.

The Pros

  • They do not require backwashing
  • They can filter particles that are quite small
  • They function well as low speeds, making them ideal for energy efficient and variable speed pumps.
  • They help conserve water due to the ability to work with variable-speed pumps and don’t require backwashing

The Cons

  • Require replacement every few years
  • The cartridges need to be deep cleaned at least once per year

Sand Filter

As the name suggests a sand filter is a big tank filled with sand. Water is pumped through it, thus filtering the debris and particles (as small as 20 microns). As time passes, particles trapped in the sand start to build up, leading to an increase in pressure, and this calls for backwashing.

This process works by pushing water through the filter backwards. Sand lasts for 6 to 7 years and the only needed maintenance is backwashing plus rinsing. However, it is imperative to match the filter with a swimming pool pump of the same flow rate.

The Pros

  • Easy to maintain
  • Excellent for big pools
  • It’s possible to utilize better sands for better filtering
  • Inexpensive

The Cons

  • Needs backwashing and rinsing which results in water wastage
  • Filters down to 20 microns, which is meager compared to other pool filters
  • Less energy efficient because of the high pressure required to push water through sand

DE (Diatomaceous Earth) Filter

This is a big tank with grids inside that are coated with diatomaceous earth powder. DE is a soft, naturally occurring rock that easily crumbles into powder. It’s essentially fossilized remains of algae with hard shells. These types of filters act like a sand filter but can filter out smaller particles with a size as small as 3 microns.

However, diatomaceous earth filters need backwashing because the pressure inside the tank tends to increase as it fills up with trapped particles. Backwashing needs to be done once per month and fresh DE powder has to be added after the process. Also, the grids in the tank need to be cleaned at least once per year.

The Pros

  • Fresh DE powder is easy to add
  • It’s the most precise, filtering 3 to 5 microns

The Cons

  • The DE powder is carcinogenic and actually, some cities restrict the use of these filters
  • It is quite expensive with high maintenance costs
  • The monthly backwashing can be daunting and leads to water wastage.
  • The grids need to be cleaned at least once per year
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AUTHOR

Shane Dwight
Shane Brown took a dive into pool care by resuscitating his sad, run-down backyard swamp over 10 years back. His DIY restoration passion project swiftly snowballed into a full-time job sharing straight-shooting, eco-friendly pool advice at OutdoorPoolCare.com. When this self-taught expert ain't researching the latest maintenance trends or testing gear on his pool, you can probably catch Shane swimming laps or just chillin' poolside with his fave folks.