Signs You Need to Replace Your Filter Cartridge

Written by Michael Dean
May 5, 2023

old and new pool filter cartridges

Keeping your filter cartridge in good condition is a crucial part of pool maintenance. Knowing the signs that it’s time to replace your pool filter cartridge will help you keep your pool clean, safe, and in top condition year-round.

Filter cartridges are an easy and safe alternative to using sand or DE filters. With relatively low maintenance required, the flexibility of using pool filter cartridges has made it one of the most popular methods of home pool maintenance. Let’s look at some signs that it is time to replace your filter cartridge in your pool.

Main Takeaways

  • You should either clean your cartridge filter when the psi rises to between 8-10 above normal or schedule a routine cleaning every 4-6 months.
  • Cartridge filters need to be replaced when there is visible damage or the cartridge is no longer cleaning the pool effectively after being cleaned.
  • You should replace your filter cartridge every 1-2 years, depending on how much you use your pool and how much debris goes into your pool.

The Importance of Your Filter Cartridge

Cartridge pool filters are one of the most popular filter options and are essential to pool maintenance and cleaning because they keep your pool free of hazardous dirt and grime build-up.

Made of artificial materials like polyester, these filter cartridges are located in your pool’s tank system. As water passes through the tank filter cartridges, it becomes clear of unwanted particles and bacteria, effectively becoming clean enough to enjoy.

Without a properly working filter cartridge, your pool is susceptible to the build-up of unwanted materials and even dangerous germs.

The Best Way to Clean Your Cartridge

You may consider cleaning if you have recently purchased a filter cartridge that has begun to slow down its cleaning potential. You need to clean your filter whenever its PSI, or pounds per square inch reading, goes up anywhere from around eight PSI to ten PSI.

Alternatively, pool owners who prefer to operate on a precise yearly schedule can choose to clean their filter cartridges every four to six months to avoid clogging.

When to Replace Your Filter Cartridge

Though cleaning your filter cartridge can help the pool filter be more effective during use, it cannot elongate its actual lifetime.

Hesitating to replace a used-up or broken filter cartridge can put your family unnecessarily at risk. Instead, pay close attention to your filter’s state and understand the signs you need to replace your filter cartridge. Here are some of the most common signs you need to replace your filter cartridge.

Your Cartridge Looks Crushed

One significant sign that you need to replace your filter cartridge is your cartridge looks crushed. This can typically happen during a big collapse of your cartridge’s inner core. The part of the cartridge that supports the filtering pleats, called the reinforcement cage, is supposed to maintain its shape and hold the filter up. If that reinforcement cage fails, the filter cartridge will effectively deflate and look like a crumpled tin cup or crushed beer can.

If you notice that your cartridge looks crushed, this is a sign to replace it. To avoid it happening again, purchase the proper size cartridge for your pool. One that is too small will likely become crushed again.

The End Caps Are Cracked

If you notice cracks at the end of the cartridge, it’s time to replace your filter cartridge. The end caps on your pool filter cartridges are important structural pieces that press the cartridge together from both signs. This offers support to your cartridge from two heavy pieces of hearty plastic.

If these plastic pieces begin to crack or deteriorate, the integrity of your pool’s filtering process will become compromised by chipping pieces of plastic.

The Pleats Are Flattened

Typically, your filter’s pleats should resemble folded pieces of paper or the side view of the pages in a small book. If this isn’t the case, there’s a chance that your pleats have become flattened.

Flattened pleats are a sign that you need to replace your filter cartridge because they can no longer capture the floating debris from your pool. Since the pleats usually appear straight and uniform, it is easy to see when they have become distorted from overuse or clogging. Don’t forget to check your band if you notice flattened pleats, as a broken band can cause pleats to flatten prematurely.

Torn or Ripped Fabric

Over time, your filter fabric, known as Remar fabric, will experience wear and tear from large dirt particle blockages, water pressure, and exposure to chlorine. This can create torn, ripped, or tattered fabric.

While some tears are easy to see due to large holes or pieces of fabric hanging off, others are microtears that are not as easily noticeable. These microtears can manifest in the form of uneven fabric texture or even a fuzzy appearance. If you notice ripped or torn fabric, it’s time to completely replace your filter cartridge.

There’s A Spike in Pressure

A high PSI, or the amount of pound-force per square inch of water in your pool, can be another good indicator that you need to replace your filter cartridge. A high PSI can suggest that your filter tank is having difficulty processing debris, and your cartridge is beginning to overexert.

When you notice a PSI, take a look at your filter cartridge. If it’s newly purchased, try giving it a soak with an overnight application filter cleaner. If this deep cleaner doesn’t help lower your pool’s PSI, it’s time to replace your filter cartridge.

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Your Pool is Dirty

The last sign you need to replace your filter cartridge is if your pool appears dirtier than usual. A very dirty pool is a common sign that your filter cartridge is not working correctly, therefore not filtering out dirt, debris, and unwanted floating materials.

If your family’s pool is commonly dirty, don’t hesitate to look at your filter cartridge today. The odds are that replacing it will drastically improve the cleanliness and safety of your pool, allowing you and your loved ones to enjoy it with peace of mind. If your cartridge is clean and working well, but your pool is still dirty, you may need to deep clean your pool.

Check out my article covering everything you need to know about swimming pool maintenance for more on this topic.

How Often Should You Replace Your Filter

So, how long do pool filter cartridges last exactly? Even if you don’t experience any of the above issues, you should be swapping out your filters at least once a year if you use your pool often or every two years if your pool doesn’t get a lot of use. Otherwise, it won’t work well, and you risk bacteria growth in your pool.

For more filter recommendations and advice, head over to my articles on common cartridge pool filter problems and the best swimming pool filters.

And that’s about it. Questions? Let me know.

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