Pool Filter Medium - The Ultimate Guide

Pool Filter Medium
Written By: Chris Tebbutt
Date Published: August 17, 2022

The swimming pool doesn't just give people a sense of comfort but offers health and recreational benefits. Whether you have a pool or you want one pretty soon, it's vital to know about the different pool filter mediums available. 

When pool owners notice with the naked eye algae or dust in the water that obscure the water clarity, they tend to think that the fault lies in their filter tank. This is why many pool owners unnecessarily replace their cartridge filter with the new version of sand filters or buy some kind of new equipment. However, you should invest in a filtration medium instead. They are often forgotten in the pool industry but remain vital to achieving better filtration and water clarity.

This is because pool filters remain a core component of swimming pools that needs to be cleaned regularly. However, choosing the pool filter medium for your pool depends on which pool you are using, and other technical factors.

These pool filters, also known as filtration mediums help in running above-ground or in-ground pools. This guide won't just talk about these pool filters but will cover how to clean your media filters to have the best experience.

What is a pool filter medium? 

This is a material that helps trap dirt and debris that oases through the filter. This term is a vital component that does a good job of cleaning your tanks or pools. There are many media including glass, zeolite, pleats, and many more. Using them depends on the pools you have and the filter fitted. 

With glass media or sand media you can filter out finer particles such as dust, and with it, your water filter lasts longer. The main point of a medium is to make your life easier by taking up half the amount of time to drain and rinse the washed algae water in commercial pools wasting much less water and time.

Moreover, this system doesn’t require valves, and, even when it is necessary, replacing the multiport valve will cause no issue with the filtering or the pump. If you wish to have a glass media medium, then using recycled glass can work. For example, beach sand and clean recycled glass can be stored in a cotton bag and placed in front of your filter. While this helps save you money, it is still recommended to make the switch and purchase a proper sand media medium, as its value offsets its initial cost. If you are planning on buying a sand media online, then make sure to do a bit of research, as pricing varies dramatically depending on the country. Filtration mediums are important, but be sure not to spend your life savings on them.

How do pool filter mediums work?

Pool filters help trap scraps, leaves, or dirt impeding free water flow in the pool. The way this filter traps dirt depends on the medium present in your filter. There are some media that attract more scraps while some trap dirt. Filtration media can be used with cartridge filters, and with it, the filter lasts longer.

Research has shown that as water travels through the filter, cleaning is done by combining two methods: mechanical entrapment and electrostatic attractions.

Mechanical entrapment is where the filter media captures dirt in pits and hollows on the media surface. Electrostatic attraction is a process where dirt is attracted to the media surface via an electrostatic charge. The stronger the media is, the more electrostatic charge is created via water passage. 

This is a very effective medium for trapping dirt from pool water. Irrespective of the pool filter media you use, the more water that passes, the dirtier the filter becomes.

Pool filter types available

Before discussing the various pool filter mediums to use for your pool, here are some important things to know.

What is a pool filter?

A pool filter is a vital component of a swimming pool that filters and cleans pool water.

Sand Filter

Sand pool filters are the most efficient and affordable pool filters for in-ground pools. These are also the first pool filters available and have been around for years. Sand pool filter makes them one of the most used pool filters used by hotel owners and homeowners. The design is simple and they are easy to maintain.

How It Works

A pool filter works when water is pumped into canisters containing sand of different sizes. This water flows via the sand and comes through the other side. 

As water flows, the sand traps scrap pieces in the pool. The more this filter is used, the more effective it is. The sand in the pool filter must be changed within 5-10 years to increase its lifespan. Some problems with this pool filter are that it needs regular cleaning, removes smaller particles, and is old-fashioned.

Cartridge pool filters

The Cartridge pool filters help screen more drifts and little particles than the sand filter. It is more expensive but more effective than its predecessor. However, because of its purchase rate, it's a bit less popular.

How it works

Cartridge pool filter works by pushing more water into the tank. The pool skimmer takes the bigger scrap material and the secondary basket helps collect small particles. The water then flows via polyester filters which trap the leftover dirt. The main drawback of this pool filter is the high price and it needs frequent cleaning.

Diatomaceous Earth Pool Filter (DE)

Diatomaceous earth pool filters are made with the fossilized remains of aquatic organisms. It normally helps absorb impurities in pool water and can also filter microscopic particles from water. 

How It Works 

It is inserted into the water and passes through pipes to a functional grid. It helps trap the DE and keeps the water clean. When water passes through the fabric-covered grid, the DE performs a filtering role 

The cons of the DE filter is that it needs to be added to the filter which increases costs. It's the more expensive type of these pool filter. Also, DE inhaled is a carcinogen that might be dangerous to health. 

Factors to consider before choosing pool filter medium 

Before talking about the various pool filter medium available, here are some things you should think about before buying them :


A pool filter medium requires detailed backwashing maintenance culture. It will require regular filtering, cleaning, and changing of elements. If you aren't keen on cleaning, you might want to avoid certain types of filter media because they get dirty quickly.


When buying these pool filter media, you should consider the cost and how much installation will take. Know your budget, and always get a filter media that is affordable.


You should only get well-designed and quality pool filter media. While some filters remove smaller dirt, others don't. Your best bet is to choose a media filter that can remove all particles irrespective of size.

Features unique to your pool sand filters

It's crucial to use a pool filter medium that is great for your pool. Also, it's a good plumb type, plumbing designs, and other factors.

The different types of pool filter media 

Here are some different types of filter media appropriate for your swimming pool :

Zeolite sand filter media 

Zeolite sand filter media is a mineral that can be found in volcanic rock. The zeolite sand filter media helps provide more than 95% more efficient processes than sand filters. It is a natural alternative that has a good structure that helps trap ammonia in swimming pools. Also, it helps control chloramine and offers a great swimming experiment.

 If you want low eye irritation, and reduced skin sores and rashes this is a good solution. It has a filtration ability of 2-5 microns. When you buy zeolite, you won't need to clean your pool filters much. This is an absorptive pool filter, however, it takes a while to do its work. Zeolite pool filter media last around 5-7 years, which means you don't need to absorb them much. However, it's a bit on the high side, but you will enjoy it. 

Glass filter media 

The Glass filter media is a top option for people who buy sand pool filters. It is made from recycled glass and provides an array of merits including a high filtration rate and backwashing. The filtration capacity of this filter media is 3-5 microns. Anytime you backwash, it requires a shorter cycle. The glass media filter is light and has a less dense capacity than the zeolite. This allows it to release dirt and debris faster. 

This filter media doesn't channel water like zeolite which implies your swimming pool water can't escape filtration. What you will enjoy with this product is that it doesn't spoil fast. It can last up to 9-12 years. For those with an Environmentally conscious pool, this glass media originates a small cat bib footprint and higher water conservation than other pool media.

 While it might be a bit expensive, it makes it even with increased lifespan, efficiency, and other pros. This is the best filter media for commercial and public pools. 

Sand filter media

Sand filter media is one of the cheapest options when talking about pool filters. It is simple and can do basic filtration functions. It has a filtration ability of about 20-40 microns. However, despite its limited functions, there are several ways to boost its efficiency. This media can last for about 3-6 years, but with proper cleaning and care, you could extend its lifespan. 

The dust of this media can be toxic and the old sand can keep bacteria and other contaminants. When using this pool media, ensure you wear a face mask. You can use cellulose fiber as a filter additive to increase the capacity of this media. This helps capture small particles.

 However be careful, because using this additive will increase the pressure on the filter and might reduce the backwash cycle time. 

Filterballs filter media 

If you are seeking a lighter alternative to the above sand filter media, you could get Filterballs. A cubic of Filterballs replaces and even outperforms more than 150 pounds of sound. The filtering ability is around 5-15 microns. Moreover, on average, these Filterballs can handle up to 25 times more debris than regular sands. It has a less frequent shorter backwash and superior quality to this filter media. 

Asides from their great filtration ability and good product weight, they provide many advantages which other filter media don't want. They provide a 49% higher flow ratio which helps limit wear and tear. Your pump saves excessive stress which leads to better energy savings. Filterballs are hydrophobic which means they don't clump together nor bind off inside the pool filters. 

This is also an eco-friendly filter media because it can be recycled easily and doesn't provide health hazards. Also, they are freeze and chemical-resistant. They tend to last about 4-6 years before you need to replace them. 

Diatomaceous earth filter media 

This is usually known as the DE powder and is an efficient pool filter media. It does a good job of keeping the pool transparent and clean. This is a natural siliceous sedimentary rock that consists of fossilized diatoms. 

Although they are natural, they can cause some serious health challenges if not used properly. When using this filter media ensure you read the instructions properly. It isn't expensive like other sand filter mediums, which appeals to many users. The filtering percentage of this product is 3-5 microns. 

Cellulose pool filter media 

The cellulose pool filter media is made from natural wood material. Cellulose is a healthy and safe media for other diatomaceous earth filters. This is non-abrasive which makes it less susceptible to wear and tear. Unlike the DE powder,  fiber has biodegradable capabilities making it the best choice for environmentally conscious people.

 It isn't just ideal for Diatomaceous pool filters alone, this is perfect for sand and cartridge filters. However, be cautious when using it with polymer chemicals. It can coagulate particles in the filter. This consists of clarifiers, metal removers, phosphate removers, and other algaecides. If this filter media is not used properly with them, 

it could clog up your filters. Using it as an additive for low-level filter media can lead to fast flogging and increased filter pressure. 

Perlite pool filter media 

Perlite is another great option when talking of natural filters which happen in volcanic rock. When it is exposed to extreme temperatures, it may increase up to 15 times its normal size. This is a lightweight product that weighs just 2 pounds. 

When you use it, you will need more for the same pool size than when you use the DE powder. Other major advantages of this filter media are less bridging, more time between backwashing, and efficient cleaning. 

Replacement pool filter media 

The replacement filter is an appropriate pool filter medium for those with cartridge pool filters. This filter cartridge comes in various sizes and colors. Before buying it, check the square footage and fabric weight. The higher its fabric weighs, the greater its filtrate ability. Also when the square footage is high, the better its pleats count. With a high pleat count, you are assured of better trappings of debris. 


Pools require the best cleaning and maintenance regime. However, to do so, you will need to understand the pool filters and the pool filter mediums used. Of course, it is not the end of the world, but for your swimming pool to be clear and heat, you need to use the best filters and filter media. However, it depends on the pool you have, the location, and if it's for commercial use or otherwise.

Article written by Chris Tebbutt
In 2016 I got my first house that had a pool and I had no idea where to begin. Over time I have learnt how to do most things myself (I am really into DIY) and wanted to share my information with other. I was one of the people who thought if water smelt like chlorine, that meant there was too much chlorine in the water!