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Signs That You Need a New Spa Filter Cartridge

We spend a lot of time thinking about spa filter cartridges - maybe too much time! They are one of our largest selling product lines, and a topic that our customers bring up quite a bit.

The question is "How do you know when to replace the spa filter cartridge?" Aside from indications of total failure, such as rips in the fabric or a cracked end cap, how can you determine when its filtering ability has diminished?

How Long Do Spa Filter Cartridges Last?

spa filter cartridge

Don't you wish that spa filter cartridges would change color or something, so spa owners could know their filter has reached its "half-life?" The fact is, each time you clean the cartridge, the fabric fibers are stretched apart a little bit more, which reduces dirt trapping ability.

By the time you have cleaned your cartridge a dozen times, it can be allowing twice the volume of matter to slip through the material and pass right through your hot tub filter. One way to determine when to replace your spa filter is to set a schedule for cleanings; when you reach 10-15 cleanings, it's time to replace the cartridge.

Many of our customers have a schedule where they simply replace the cartridge on an annual basis at the same time each year.

How Often Should You Clean a Spa Filter?

Spa filter cleaner

Another way to easily tell when the spa filter has reached its half-life is when the time interval between cleanings decreases. If you were formerly able to maintain water clarity or proper filter pressure with a monthly cleaning, but now it has to be done every two weeks, you can assume that your filter cartridge is clogged with minerals or oils.

Spa filter cleaners can help remove this gunk, or it may be time to just replace the hot tub filter(s).

Spa Water Clarity

Another way to measure your cartridge effectiveness is to look at your spa water. Is it as clear and sparkly as you want, or does it look dull and dirty?

You may find yourself compensating for a weak spa filter by using more sanitizer than you used to, or having to run the spa filter longer in order to achieve the same degree of water clarity in your spa.

Spa Filter Tips

To help your spa or hot tub filters last longer, follow these tips:

  1. Always have a spare spa filter to use while cleaning and drying the dirty spa filter.
  2. Drying after cleaning helps kill any remaining bacteria and contaminants.
  3. Use a spa filter cleaner every 3-6 months to remove oils and mineral deposits.
  4. Don't use a brush while cleaning, and don't use a pressure washer.
  5. Don't use any household chemicals, soaps or detergents.

To keep your spa sparkling and safe to use, replace your spa filter cartridges every 12-24 months. With our low prices, there's no excuse not to buy new filter cartridges for your spa or hot tub!

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Leslie’s makes every effort to provide accurate recommendations based upon current ANSI/APSP/ICC-5 2011 (R2022) standards, but codes and regulations change, and Leslie’s assumes no liability for any omissions or errors in this article or the outcome of any project. You must always exercise reasonable caution, carefully read the label on all products, follow all product directions, follow any current codes and regulations that may apply, and consult with a licensed professional if in doubt about any procedures. Leslie’s assumes no legal responsibility for your reliance or interpretation of the data contained herein, and makes no representations or warranties of any kind concerning the quality, safety, or suitability of the information, whether express or implied, including, without limitation, any implied warranties of merchantability or fitness for a particular purpose.