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How To Clean Pool Cartridge Filters

How to clean pool cartridge filters

If you live in the southern United States, you probably find solace in your pool during the warmer months of the year. Some days, it can seem like the only way to enjoy time outdoors is to spend the day cooling off in your home’s backyard pool.

Still, though, as much as we use our backyard pools, it’s easy to take them for granted. Especially during the summer months, we want to assume our pools will be clean and ready to use at a moment’s notice. While it’s safe to assume the pool’s filter will keep it clean, many homeowners overlook the fact that the filter itself needs to be cleaned periodically. 

How To Clean Pool Cartridge Filters

In this post, we’ll discuss the types of filters you might be using in your pool, how they function and how and when you should clean your filters. Read on to learn the dos and don’ts of cleaning your filter and everything you need to know before doing so.

Pool Filter Basics

Before cleaning your pool filter, it’s important to know why it’s important to do so, the function it serves and how it works. A pool filter is simply a device that filters out, or separates, the water from the dirt and other particles to keep your pool clean. Think of it like a pasta strainer: water filters through the holes while the larger pasta pieces remain in the strainer.

Most filters are comprised of cartridges made of non-woven, spun-bonded polyester fabric that creates a tight mesh through which water can pass through, but dirt cannot. This keeps your pool water clean. Over time, though, the dirt it traps begins to build up on the fabric. Once this starts to occur, the material loses its ability to properly filter the water, or separate the dirt from the water. When this becomes apparent, it’s time to clean your filter.

Pool filter cleaner homemade

Types of Pool Filters

There are three types of pool filters available: sand, cartridge and Diatomaceous Earth, or D.E. filters. The main differences between the three is the kids of filter media, which can be found inside the tank, each uses. No matter the type of filter you have, though, they all need to be cleaned periodically. Let’s discuss each in depth.

Sand Filters

Sand filters are incredibly common among homeowners, as they are typically the easiest filters to use of the three. In a sand filter, pool water is pumped into the filter where the dirt and unwanted materials gets trapped in the sand. The sand is tightly compacted, thus, the design makes it hard for water to travel through but even harder for dirt.

While it might seem counterintuitive, sand filters actually work more efficiently when slightly dirty. That’s because small particles that are left behind reinforce the tightly packed materials. Because of this, sand filters should only be deep cleaned when the homeowner notices an increase in pressure, or when the filter’s pressure gauge reads a 7-10 pound increase over normal operating pressure. It should, however, be backwashed a handful of times between deep cleans. A good schedule to follow for cleaning sand filters is doing so at least every season.

Replacing the sand in your sand filter, though, is slightly different. As such, it’s best to contact your local pool professional to best determine the frequency in doing so.

When it comes time to backwash your sand filter, you’ll want to begin by cleaning the debris trapped by the sand. Be sure the to turn the pump off before changing the position of the main valve. Otherwise, you’re likely to break a part of the filter. Once you’ve ensured that the pump is off, move the lever to the “backwash” position to restart the pump. The pump will start running the water through the filter; the water will run clear, then dirty, then clear once again to indicate the cycle is over. After this process, reset the valve back to its normal setting.

Keep in mind that this process does remove water from the pool, so be sure to check the water levels before you begin and don’t begin the cleaning process if the water is already low.

How to clean pool cartridge filter algae

Cartridge Filters

Of the three filters mentioned, the cartridge filters have the highest capacity of all them all. In fact, these can trap twice as much dirt and debris as a sand filter. It can do so because it has a larger filtration area that allows the water to move through the cartridge easily while still trapping smaller particles. Despite its larger size, a cartridge filter is much easier to maintain. It’s also considered the most common and can typically be found behind a flap or screen in the wall of your swimming pool.  

To clean a cartridge filter, you’ll want to set aside ample time to do so properly. First, turn off the filter system and begin to allow the air to bleed slowly from the filter by turning the air relief valve. Next, remove the clamp that holds your filter together and remove the top section of your cartridge filter to see inside. Once you’ve successfully removed anything holding the cartridge in place, take out the cartridge elements and inspect them for any damages. If there are any cracks or breaks in the plastic, purchasing a new filter cartridge is strongly suggested, as small cracks can significantly decrease a filter’s effectiveness.

After you have removed the cartridge, coat the parts with a filter cleaner and follow the product directions for how long to let it sit before rinsing it off. Then, you’ll use a hose with an attachment to remove dirt and debris from between the pleats of the cartridge.

Once it’s cleaned, place the cartridge elements back inside and securely place them where they once were. Be sure all cartridge elements are secured properly before turning on the system. After your system is running again, release any excess air in the system by opening up the air relief valve at the top of the filter tank until water consistently sprays out of the valve.

Cartridge filters are ideal for above-ground pools, and can, unlike the others, be used in pop-up swimming pools as well.

D.E. Filters

Diatomaceous Earth Filters are different from the other two options in that the D.E. is the filter media itself while the other two filters are made up of various components. D.E. is an extremely fine powder or crushed rock that is “composed of chemically inert, fossilized remains of billions of microscopic algae-like organisms, called diatoms.” Because D.E. filters are more compact and can filter out smaller particles than the other two filters, it’s considered the best choice for residential pool filters. The downside, though, is that it’s most expensive type of filter available.

Though backwashing is required just once or twice a year for D.E. residential pool systems, you’ll want to keep an eye on the pressure gauge to ensure you clean or change the system when needed. When the pressure gauge falls below eight pounds, it means it’s time to change it out.

Changing or adding new D.E. is actually easy to do. Simply drop the new D.E. into the skimmer and the pump will suck the D.E. into place. Keep in mind that the biggest mistake people make when doing so is not adding enough powder.

Pool cartridge filter cleaning tool

Pool Filter Cleaner: Homemade or Store-Bought?

You can purchase pool filter cleaner, but some pool owners choose to make their own. One method is to fill a bucket with warm water so that it’s deep enough for the cartridge to be completely submerged. Then, add one cup of liquid dish soap or dishwasher detergent for every five gallons of water. Allow the filter to soak anywhere from one to eight hours before you remove it and rinse it off with the hose.

Another way to make your own pool filter cleaner is to mix a cup of trisodium phosphate for every five gallons of warm water. Fill your container enough to submerge your filter. Allow your cartridge to soak for somewhere between one and eight hours before you remove the filter and spray it off with water from your hose.

Pool Cartridge Filter Cleaning Tool: What Do I Need for the Job?

Many pool owners use a garden hose to clean their pool filter cartridge, but there are also tools available to make it easier. Filter flossers, pool filter wands and water wand cartridge cleaners all attach to your hose to more precisely direct water flow to get your filter even cleaner. Keep in mind that while some water pressure is good, too much can damage the fibers of the filter, so avoid using a pressure washer to clean your cartridge.

If you want to take all of the guesswork out of cleaning your filter, you may want to opt for an automatic filter cleaners. These devices rotate your filter and deliver sprays of water throughout your cartridge. The design allows the dirt and debris to fall out of the filter as it is being sprayed with water. Automatic filter cleaners come in several sizes and clean most cartridges in just a few minutes.

Can I Clean Pool Filter Cartridge With Bleach?

To remove a stain from a piece of clothing, you might soak it in bleach, so does that mean that you can soak your cartridge in bleach? Companies that sell pool chemicals advise against doing so, since bleach can damage the fibers of your filters and thereby shorten your filter life.

Cartridge manufacturers offer a range of products to help keep your filters clean. Some pool owners make cleaning solutions out of detergents or vinegar which are more gentle on your filters over time.

Clean pool filter cartridge with bleach

How to Clean Pool Cartridge Filter With Algae Coating

In some cases, you’ll disassemble your pool filter cartridge and realize that your filter is covered with algae. In these cases, you’ll want to soak the filter in a solution of one part muriatic acid to 20 parts water. When the bubbling stops, rinse the filter. If that doesn’t resolve the problem, you might need to soak it a commercially-available filter cleaner or a solution of one cup of trisodium phosphate to five gallons of warm water.

Why Are Filters Necessary?

Though it might seem like an obvious chore, cleaning your pool, and realizing the importance of doing so, is often overlooked by homeowners. For starters, unkept pools and filters can lead to more serious backyard problems down the road, and can ultimately cause more homeowners more money.

A clean pool is also essential for you and your family’s health. The cleaner your pool water, the less likely it is to contain parasites, waterborne illnesses and bacterias. The same applies to the environment. If your pool becomes dirty or contaminated, you run the risk of letting dirty water seep into your neighborhood’s waterways and environment.

Trust ABC For All Your Pool Needs

Having a pool on your property is great, especially when you live in warm climates. As with most additions to your property, however, having a pool adds a responsibility and added chore to your routine maintenance list. Luckily, ABC Home & Commercial is here to help. Our team of licensed specialists can fix any pool-related problem, whether it’s a faulty pump or filter or any other mechanical problem. We can demonstrate how you can properly maintain your home’s pool system or take care of your pool maintenance for you. We look forward to helping you keep your pool crystal clear for years to come.

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