Tag Archives: Cartridge Filters

Expert Help for Choosing the Perfect Filter Cartridge

Filter Cartridge Diagram

Do you need to replace the filter cartridge in your pool or spa? Knowing which replacement model to choose can be confusing. Use the easy step by step guide below to make sure that you choose the correct option!

  1. Measure the outside diameter of the end cap. Be sure to use exact measurement (+ or – 1/32″).
  2. Measure the existing cartridge length. The length is calculated from end cap to end cap and should be exact (+ or – 1/16″). Be sure to exclude any handles or extensions from this measurement.
  3. Measure the top inside diameter. Again, be sure to use exact measurements (+ or – 1/32″).
  4. Do the same with the bottom inside diameter.
  5. Note the name and model of the filter that the cartridge came out of.
  6. Next, you will have to identify the correct top and bottom type. These are the types that you will see. Note the one that most closely matches your filter cartridge.

Open Top/Bottom

Open Top/Bottom w/Gasket

Closed Top

Closed Top
w/ String Handle

Castle Top

Molded Cone


Open Bottom
w/ Male Slip Fitting

Open Bottom
w/ ThreadedFitting

With all of the information that you have now gathered, you are ready to call or visit your pool supply source with the knowledge needed to make an informed purchase!

Pool Filters Explained

No matter how diligent we may be with our pool cleaners, dirt, debris, and other unsavory bits in our pool water can elude our pool cleaning devices.  Luckily, pool water gets pumped through the pool’s filter system where particulates in the water become trapped.  A swimming pool’s filter system is an essential component for maintaining clean, safe water.  What type of filter system does your swimming pool use?

The three existing types of swimming pool filters are Sand Filters, Cartridge Filters, and Diatomaceous Earth Filters (DE Filters, for short).  Here’s how they each work:

Sand Filters

Sand FiltersSand filters, often considered the easiest filters to own and maintain, use a specially graded sand as the filter media. Water enters the tank through a diffuser.  As the water goes down through the bed of sand, the dirt and debris are trapped between the grains of sand.  When the water reaches the bottom of the filter, it enters the laterals and is returned to the pool.  Sand filters trap debris as small as approximately 40 microns in size.  Anything smaller than 40 microns will often pass through the filter and get circulated back into the pool.



Cartridge Filters

Cartridge FiltersOne of the most popular choices among the filter systems is the cartridge filter because it can be removed and cleaned with out backwashing, which saves pool-owners time and energy.  Cartridge filters use a paper-type cartridge as the filter media.  They do not filter as finely as DE filters, but they produce about the same water quality as sand filtration.  In the past, cartridge filters were considered a nuisance to maintain, but over the years, manufacturers have developed newer filters with enough surface area (300-500 square feet) to require cleaning only once or twice each year.



Diatomaceous Earth (DE) Filters

Diatomaceous Earth (DE) FiltersDE filters are the most effective of the three filter systems.  Diatomaceous earth comes from a naturally occurring sedimentary rock that crumbles easily into a fine powder.  The DE filter has plastic grids covered with a plastic type of fabric.  A layer of the diatomaceous earth filter powder covers the grids and filters the water.  As the water passes through the filter powder, any debris down to 5-8 microns is filtered out.  Because the DE is much finer that sand, it is able to filter much more effectively than a sand filter or cartridge filter.

Flossing Removes More Debris From Pool and Spa Filters

Just as flossing your teeth prevents debris from building up, flossing your pool and spa cartridge filters does the same.  Using a Filter Flosser Deluxe Filter Cleaner allows pool owners to maximize the life of pool and spa cartridge filters while reducing the amount of time, energy, and water spent on regular filter maintenance.

Using the Filter Flosser is easy.  Simply attach your garden hose and spray the filter for a deep down clean.  The unique curved nozzle design provides an extended cleaning area (more than double of other cleaners) helping you to clean 50% faster and use 50% less water. The high pressure water and air agitation reaches deep down between pleats for more thorough cleaning and removes all of the built-up dirt that shortens the life of your cartridge filters.