Which Pool Filter Is Best?

Every swimming pool needs a pool filter. Without a functioning pool pump and filter, your water will inevitably turn green. However, which pool filter is best: sand, cartridge, or D.E. filter? We often encounter pool owners who are struggling to decide whether to keep their cartridge filter or to switch to sand or D.E.

Each filter has its own pro’s and con’s and each pool owner has his/her own list of priorities, as well.  It’s important to keep your personal pool priorities in mind when choosing your filter.

The best pool filter for you is one that aligns best with your pool needs.

Sand Filters

The most traditional type of pool filter is the sand filter. Of the three types of filters, sand filters are the least effective. They filter particles that range from 20-40 microns. Sand filters use sand to filter dirt and organisms from your pool water. Once the debris is at capacity or full, the pressure inside the filter increases.

Related image This is an indication that you need to backwash the filter. In short, backwashing is simply running the water inside the filter in reverse direction. With the help of your multiport valve, you can easily switch valve positions from filter to backwash. However, be wary because backwashing can also create other pool-related issues.

Before purchasing a sand filter, there are a few things you should keep in mind. First, if you continually backwash your pool, you can disrupt your water chemistry and affect the water levels. After backwashing your pool, you might find yourself rebalancing and refilling your pool. As a result, you spend more money on chemicals and water. Not to mention, you also have to figure out where you are backwashing the water.

You also need to purchase a valve to operate a sand filter. In many cases, the valve will come with the filter. However, that is not always the case. Make sure that you double- check the contents of the filter you want to purchase.


  • Typically, the most compact and affordable
  • Minimal maintenance
  • Easy to clean (backwash)
  • Straightforward operation
  • Replace the sand every 5 to 7 years



  • Lower filter ability compared to cartridge and D.E. filters
  • Constant backwashing can throw off your water balance
  • Higher spending costs on chemicals and water
  • Need to determine where you will backwash the water to


Cartridge Filters

The second type of pool filter is the cartridge filter. Cartridge filters take advantage of pleated cartridges by maximizing the square footage of the filter. The larger the surface area, the more dirt particles you can filter out. Cartridge filters can capture debris as small as 10-15 microns. In terms of efficiency, cartridge filters fall in the middle. Image result for how a cartridge filter worksHowever, they are the easiest to maintain.

When the cartridges are dirty or the pressure in your filter rises, it is time to clean them. Depending on the water chemistry, most pool owners clean their cartridges every six months. Cleaning is as easy as using a garden hose to rinse them off. There is no need to backwash a cartridge filter.

Cartridge filters work best at slow flow rates. An overly-sized pool pump has the potential to push the water straight through the cartridge filter and bypass the filtering stage altogether. It is important not to oversize your pool pump, especially when using cartridge filters. However, this also makes cartridge filters more efficient. Cartridge filters utilize and waste less water. Unlike sand filters, using a cartridge filter saves you money on chemicals and water.


  • Low maintenance
  • Easy to clean and replace filter cartridges
  • The easiest type of filter to install



  • Heavy algal build-up can potentially clog the cartridge. You will need to rinse the cartridge more frequently.
  • Depending on the make and model, the price of a replacement cartridge can be high
  • Works best with slow flow rates


Diatomaceous Earth (D.E.) Filter

If you are looking for the best way to filter your pool, D.E. filters are the way to go. Although they are most similar to sand filters, the approach to filtering is much different. Diatomaceous Earth, or D.E., filters use fossilized remains of diatoms to filter the pool. They collect particles and debris as small as 2-5 microns. Of the three types, a D.E. filter provides the most thorough cleaning.

Image result for how a d.e. filter works

D.E. powder coats the filter grids and allows water to pass through, trapping the dirt to one side. However, like sand filters, you clean D.E. filters by backwashing. Like most filters, you can monitor your pressure gauge to determine when your filter needs backwashing.

In addition to backwashing, D.E. filters require pool owners to clean the filter elements routinely . You can remove the grids and hose them down with a standard water hose. You can also soak your grids, which removes all of the dirt, oils, minerals, and stains from the filter fabric. This is one of the reasons why D.E. filters require the most maintenance.


  • Best filtration ability
  • Can go a few months without backwashing
  • Grids can last several years if properly cared for



  • You must add D.E. media to your grids after every backwash
  • Higher costs related to maintenance
  • Disassembling the filter grids can be time-consuming
  • D.E. is a known carcinogen and you should refrain from inhaling it
  • Like sand filters, you also need a backwash valve to operate the filter


Poolside Chat: Should You Switch From a D.E. Filter to a Sand Filter?

Poolside Chat is INYO Pools’ You Tube show where hosts Matt and Rob answer pool-related questions submitted by pool owners across the country. In a recent episode, Matt and Rob tackle whether pool owners should switch from a D.E. filter to a sand filter.

Watch the video below to hear some of the key points to keep in mind if you find yourself switching pool filter types.


Which Pool Filter Is Best?

Choosing a pool filter is an important decision for your pool. However, at the end of the day, you need to pick a filter that caters to your pool and personal needs. The filter that a pool owner in Florida chooses may not be the best decision for a pool of the same size in New York.

Before choosing your new pool filter, consider factors such as initial costs, maintenance routines, maintenance costs, costs associated with repairs, and the ease of operation.

If you are looking for the absolute best filtering option, not considering maintenance routines and costs, we’d recommend a D.E. filter. However, if you want something more economical and budget-friendly, you might want to consider a sand filter.

For more information, check out our video below on how to select an inground pool filter. 

9 thoughts on “Which Pool Filter Is Best?

  1. Do not sand filters now use a glass medium which makes them a better filter than you state in this blog? Glass has a tighter turbid catch, with an ability to filter down to 9 microns. Some brand claims go as low as 3 microns. This DE-quality filtration can be achieved without chloramine-producing flocculants and shock treatments, which is one reason glass is most commonly found at indoor pools where air quality is a top concern. I do believe your blog is way outdated when it comes to sand type filters. Then can be as good as DE type and certainly better than filter types!

  2. I look forward to INYO”S response to Dave’s commentl

    One additional comment would be helpful. The cleaning of a cartridge filter can be a bit prohibitive in respect to costl If you plan to use a pool cleaning company be sure and ask what they will charge for the cleaning of the cartridge(s). Also determine the cost of replacement of the cartridges.

  3. Hi,

    Thank you for the very informative article.

    I need to replace my filter (currently Pentair DE FNS 4820), and I am thinking of switching to cartridge filter as I have SWG and Solar Heater, so I want to reduce my Head Loss.

    However, due to mesh grid cover, and landscaping, my pool is always dirty in the spring, so I need to clean my current filter (Pentair FNS 4820) at least twice, and I hate dealing with DE.

    That’s why I am thinking of going with the big cartridge (over 500 sqft), but I was told by my Pool guy, that I would have to clean them even more frequently than the DE filter. Does this sound right?

    Which filter would need less cleaning Pentair Quad DE 100, or (Pentair Clean & Clear 530 Sq feet ?

    My pool is 42,000 gallons.


    1. The tech who told you that the four cartridge system would require more cleaning/maintenance then the DE was incorrect. Users of the large cartridge filters can expect to clean their filter may twice a year, if it sized correctly. Just compare the square footages of the filters, 100 square feet for the Quad100 and 530 sq ft for the Clean and Clear; which one is going to fill up faster if treating the same water. Look at it this way, if those square footages were sizes of closets, which one would get cluttered and clogged quicker if you were shoving the same amount of junk, at the same rate into them?

  4. Ok,

    I have had all three filter on three different pools. Here’s my take after 30 years.

    Like the article above sand filters have the pros and cons and agree with everything!

    One guy wrote in about the glass sand! Lol sand is glass. Well, I tried the Z- bright sand that is supposed to be better.. guess what it was for a month and kept building up pressure and water volume down to the point I was backing washing every week just to disrupt the sand for better flow. Nope!

    D.E. I totally agree with the article! Still pretty nice polished water.

    Now for my trick!, I run cartridge filters. When new or after you clean them I add about 5 cups of DE right after start up. This is on a four cartridge filter. This is just enough DE to polish the water and keep all the dirt from sticking to the filters. Now when I take them out for cleaning they hose right off nice in clean… this method has worked for me for many years! DE is cheep and it catches all the small stuff.. my filter only runs about 2 1/2 psi and when it hits 10-12 psi clean the filters. Also my pump is full solar, no grid! About 8 hrs. A day pump for free.. of coarse I live in Arizona with 350 days of sun..


    1. Hi Steve.
      My name is Ed
      I live in Peoria. I have had the problem of sand getting into pool while pump is on. I replaced everything inside the Pentair Triton 2 T100, orTR100. Still sleeping into pool. Pool was here when I purchased 4 years ago. I would like to know what equipment you have. Reviews on the filter I have are very good, yet I can’t figure out why this happens. I did have a pool guy “Happy Jack” out when I had all the sand out. Had no idea why as well. I don’t mind paying for quality. It originally had a valve type plunger for back washing. I put a lever valve on it. Same thing.

  5. All of my pool equipment needs to be replaced after lightning struck a tree next to the filter. I have a large Gunite pool. Looking for recommendations as to what brand of filter/ salt chlorinator to purchase since I need the entire package? Current equipment is Jandy and my current system has been discontinued.

    1. If you want a recommendation for replacement equipment, please list the model numbers of the equipment you currently have. This information will give us an idea of the equipment parameters needed for your pool.

      The term large gunite pool is 20k gallons in one person’s mind, while 40k gallons to the next person. We need more to go off of.

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