On a hot, summer day, there’s nothing like jumping into a sparkling blue, refreshingly cool swimming pool. It’s important to maintain the appearance of your swimming pool throughout the swimming season because it will maintain the value of your investment. In your first defense against dirt, grime, or fungus, pool filters can be extremely helpful.
When looking to maintain your swimming pool, there are three major pool filters that you’ll be able to choose from. Even though each filter has water-cleaning capabilities, there are advantages and disadvantages to both. Selecting the best pool filter will help keep your pool blue and sparkling through the summertime.
What is a pool filter?
Pool filters are designed to remove any dirt or grime from the water and to keep your pool looking crystal, clear, and blue. Without a good filtration system, your pool could become unsanitary and a health hazard. To operate, the pool filter sucks out water through and out of the other end, where it is then pumped back into the pool to stay clean.
When searching for a pool filter, you’ll have three major types of pool filters to choose from. Each filter has its advantages and disadvantages, so it’s important to pick the best one that is suitable for your pool. The three major types of pool filters are:
- Sand filters
- Cartridge filters
- Diatomaceous Earth (DE) filters
What are Pool Filters Made of?
When trying to make the best choice for your swimming pool, it’s important to understand the materials that are used in making pool filters. The two major materials used in making pool filters are Polyester Mesh and Nylon Mesh.
Polyester Mesh
Polyester Mesh has high strength, durability, is resistant to corrosion, mold, mildew stains, and wear. It provides excellent stability and is very easy to clean. In addition, Polyester Mesh is more resistant to heat and rays from the sun, which makes it suitable for outdoor swimming pools.
However, Polyester Mesh material tends to be on the rougher side. It also is not the best for bending, which could make it less than ideal in situations where elasticity is needed.
Nylon Mesh
Nylon Mesh is a synthetic plastic that is high in strength, lightweight, elastic, flexible, resistant to temperatures, has a smooth feel, and is easy to clean. Nylon Mesh is great for long-term use, and its smooth feel aids in removing dirt, which makes this a great material to use for swimming pools.
However, Nylon Mesh can absorb and retain too much water, which may cause it to lose its shape in very humid or wet environments. It also can degrade while in direct sun, which could make it a deal-breaker when using it for swimming pools.
Is it Safe to Use Pool Filters?
Yes, it is safe to use pool filters, even if you’re swimming in your pool while it’s running. If you don’t have a filter for your pool, your swimming pool will collect dirt and bacteria, which could make it a growing environment for diseases. Without a pool filter, your swimming pool will turn into a filthy, unswimmable mess.
Is it Possible to Have a Safe Pool Without Pool Filters?
It is possible to have a safe pool without a pool filter, but only for a short period. The longest you’ll want to go without a pool filter is around a week. Factors such as weather, temperature, and how clean your pool was when you turned off your filter all play a role.
How Pool Filters Work
The three types of major pool filters are Sand Filters, Cartridge Filters, and Diatomaceous Earth (DE) filters. Below, we’ll dive into how each filter operates and the pros and cons of each.
Sand filters work by moving water from the very top of your tank through the sand to the very bottom of your tank using high pressure. When the water starts to move down, the grains of sand will catch any dirt or grime that is caught in your pool. This process will keep occurring until your sand becomes dense and needs to be back-washed (cleaned).
Cartridge filters work by pushing water from your pool into the tank. This will have a skimmer that can catch larger amounts of dirt and a secondary collection that will collect anything that is missed. After this process, the water will then go through a polyester filter, where dirt will attach to the screen to make way for clean water.
The DE filter operates by adding DE powder that contains a type of algae to your pool filter. While acting like a sponge, this powder will absorb any dirt or debris that comes into contact with your pool filter and will get them out by using a skimmer box. If you have a DE filter, you should keep an eye on the gauge, as any reading between 8-10 lbs requires a backwash (cleaning).
| Filter Type | Pros | Cons |
| Sand | Low maintenance | Lowers your pool water from cleaning |
| Sand | Inexpensive | Throws off chemical balance |
| Sand | Removes small debris | Needs to be changed ever 5-8 years |
| Cartridge | Uses low pressure to save on energy costs | Cartridges must be washed |
| Cartridge | Low wear and tear | Not ideal for large commercial pools |
| Cartridge | Easy maintenance | Costs more for purchase and maintenance |
| DE | Filters fine debris | Messy |
| DE | Inexpensive | Must be changed frequently |
| DE | Maximum efficiency | Water waste potential |
Pool Filters, Dirt, and Age
Pool filters tend to work better when they are dirtier because they can trap dirt that is in the 20 microns range. In a pool that is well-balanced and clear, pool filters will remain clear. A sand filter that is cleaned might only clean up to 40 microns, but as more dirt becomes trapped, it will clean more.
Flow rates and the age of your pool filter also determine how well your pool filter performs. If you have a high flow rate, this will give you poor filtration and will allow small dirt and debris to flow right through your pool filter. As your pool filters age, their dirt-trapping power will become cut in half and should be replaced.
Which is the Best Among Sand, Cartridge, and DE?
When it comes to choosing the best pool filter, it boils down to your personal choice and needs. In addition, when choosing the best pool filter you’ll want to consider efficiency, media lifespan, price, replacement cost, water usage, maintenance, and repair frequency.
Sand Filters
When it comes to efficiency, sand filters are the least effective of the pool filters, filtering dirt and other debris that are 20-40 microns. When considering maintenance, they are the easiest to maintain and only require backwashing (cleaning) when the gauge reads 8-10 lbs over the recommended startup. The average price for sand filters will run you anywhere from $300-$2,000.
If you’re looking for a sand filter for an in-ground pool, this will cost between $450-$1,200. For pools that are above ground, sand filters will cost between $300-$500. For replacements in some circumstances, you may only need to replace the sand, which could cost you between $25-$35 for a fifty-pound bag.
In terms of lifespan, a sand filter will last anywhere from three to seven years depending on how much you use it. If you use your sand filter frequently, it may need to be repaired for around 5 years. In terms of water usage, you will use around 500 gallons of water when backwashing.
Cartridge Filters
In terms of efficiency, cartridge filters will save you money on both energy and water with savings of around 90%. This is a lot more savings you’ll receive when compared to a sand filter. When considering maintenance, you should clean your cartridge filter every 3-6 months to remove any dirt or debris.
If you’re looking for a cartridge filter, you can expect to pay anywhere from $200 to $1600. To replace your pool filter, you can pay as much as $125. In terms of lifespan, a cartridge filter will last you anywhere from 3-5 years depending on how much they are used and how well they are maintained.
Cartridge filters may need to be repaired every 3-5 years depending on how well you’ve taken care of them. In terms of water usage, you will use around 100 gallons of water compared to sand and DE filters.
DE Filters
When it comes to efficiency, DE filters are the most efficient pool filters on the market as they filter down to 3-5 microns. This is barely noticeable as they filter even the tiniest of particles. DE filters can last you anywhere from 4-5 years with proper care and maintenance.
After more than ten seasons, you may notice the fabric starts to become brittle. The lifespan of your filter will depend on how dirty your pool gets and how well the chemical balance of your water is maintained. The price of a DE pool filter will average as low as $500 and as high as $2,000.
If you need to have your DE filter replaced, you can expect to pay anywhere from $250-$1,500 depending on the size of your filter. In terms of water usage, the size of your pool will depend on how much DE you need to use. For a 10,000-gallon pool, you will need to use around 1 lb of DE per week.
To clean your DE pool filter, it should be cleaned about once every month or when it’s 8-10 lbs over the starting pressure. To clean your DE filter you’ll backwash, clean the grid, and then add the new DE. Your DE filter should be taken apart about every three months to do a thorough inspection or repair.
| Filter Type | Cost |
| Fibropool Sand Filter | $299.00 |
| Hayward W3S244T Sand Filter | $599.00 |
| Hayward W3S210T Pro Series Sand Filter | $459.00 |
| Hayward W3C12002 Cartridge Filter | $599.00 |
| RX Clear Radiant Cartridge Filter | $289.00 |
| Hayward W3C500 Star Clear Cartridge Filter | $319.00 |
| Hayward W3DE6020 DE Filter | $1,249.00 |
| Pentair 180007 DE Filter | $1,029.00 |
| Hayward W3EC40C92S DE Filter | $879.00 |
Common Pool Filter Problems and How to Fix Them
When taking a swim on a hot summer’s day, your pool filter is one of the most important parts to help maintain the health of your swimming pool. It’s important to know when your pool filter is not acting properly and how to fix them. Below, you’ll read about some common problems with the sand, cartridge, and DE filters and how to fix them.
Sand Filter Problems and a Guide to Fix Them
The most common problems you’ll have with sand filters are:
- Cloudy water
- Leaking
Cloudy Water
If you notice your pool has cloudy water, this is often a sign that you have algae in your pool. In most cases, this would mean you need to add more shock to your water, however, in other cases, this may be caused by high pressure building up in your filter. If your sand filter reads 8-10 lbs over its startup reading, this means it needs to be back-washed.
In most cases after backwashing, this will return your reading to normal. However, in some cases, you could have a bad gauge, need new sand, or have a problem with the valve. If this is an extreme case, you’ll want to contact someone who specializes in pool maintenance to help you fix the problem.
Leaking
In some cases after backwashing, you may notice your filter leaking from the line. If your leaking continues even after backwashing, this could mean there’s a problem with your valves, o-rings, or your spider gasket seals. To fix the problem, this may easily be done by resetting your parts or replacing them.
If you are experiencing a leak, this could also be from your tank. If you have a leak in your tank, this requires your tank to be replaced. In this case, it would be on the cheaper side just to replace your whole filter.
Cartridge Filter Problems and a Guide to Fix Them
The most common problems you’ll have with cartridge filters are:
- Inconsistencies in pressure
- Leaky Clamp
- Chemicals are not balanced
Inconsistencies in Pressure
Inconsistencies in pressure can happen from a build-up of dirt and debris. If your pressure is too low, dirt or debris could be causing a blockage to occur, or you could have a broken valve.
To fix this problem, make sure you are inspecting your cartridge at frequent intervals and make sure you clean it every three months. If you continue to have problems, you’ll want to have maintenance come and take a look at it for further problems.
Leaky Clamp
If you have high pressure or a clamp that is not properly installed, this could cause a leaky clamp. Over time, due to movements, this could cause your clamp to become loose or crack.
To fix your leaky clamp, you’ll want to turn your pump off, drain your tank, and remove the clamp’s band to separate the body and band in two halves. Next, you’ll want to clean the gasket with a cloth, inspect the ring for any wear and tear, and lubricate it before reinstalling. Once that is finished, you can turn your pump back on and see if there are any more leaks.
Chemicals are Not Balanced
Unbalanced chemical levels can be caused by not having enough chlorine in your pool, time, algae buildup, heat, or the quality of your water.
To fix this problem, your levels should be anywhere from 80-150 ppm. Depending on the size of your pool, your chlorine levels should be between 1-3 ppm. Make sure you are checking your chemicals often to keep them at a balanced rate.
DE Filter Problems and a Guide to Fix Them
The most common problems you’ll have with DE filters are:
- Leaky Drain Valve
- Calcium Clogged
Leaky Drain Valve
The majority of DE filters have an o-ring. With DE filters, you should keep this ring lubricated to avoid a leaky drain valve and use tape (Teflon tape) on the treads. Make sure that you don’t over-tighten your plug or you may cause a crack while assembling.
Calcium Clogged
When you have calcium clogs, this clogs up your DE filter’s pores of the grid, which will slow the water flow and raise your filter pressure. To resolve the minerals and restore proper flow, you should soak your grids in a mild solution to clean them.
How to Maintain Pool Filters
Maintaining your pool filters will depend on the type of filter you have. If you have a cartridge pool filter, you’ll want to use a garden hose to clean it. You’ll want to clean this every four to six weeks and soak it in 1 part water and 2 parts cleaner.
To maintain your sand filter, you’ll want to use a sand filter to disinfect the dirt particles. Make sure to follow the proper instructions when replacing your sand filter to avoid any damage. If you have a broken sand filter, you should repair any interior parts before deciding to buy a new filter.
To maintain a DE filter, you’ll want to give it a regular cleaning once a month to avoid calcium buildup. The Grids of DE filters are very long-lasting when properly taken care of.
How to Clean Swimming Pool Filters
Swimming pool filters help to keep your swimming pool clean and sparkling blue. While in use, pools can collect dirt, hair, sunscreen residue, and more. Pool filters help keep the waters clean for you to swim in to prevent your body from absorbing anything harmful.
Cartridge Filters
Cartridge filters are the easiest of the pool filters to clean. The only thing you need to do is remove the filter from the pool, hose it down with a garden hose, and put it back into your pool. To properly clean a cartridge filter you’ll want to turn off your pump, remove any air from its system, remove the clamps, remove the top of your filter, and inspect the cartridge for any wear and tear.
Next, you’ll want to spray down the filter with your garden hose. After that, check the o-ring to see if it needs lubrication. Finally, replace your filter top, turn it back, and open the air relief. Make sure the cartridge filter’s PSI is in the normal range.
Sand Filters
Cleaning a sand filter has similar steps, but it’s a little tougher. First, to clean it, you’ll need to backwash it. You’ll need to attach a backwash hose, turn your system off, turn the valve to “backwash”, let the water run for a minute to close it out, and then set the valve to rinse.
Next, you’ll turn your filter back on and let it run for 30 seconds on a rinse cycle. Finally, you’ll turn your system off, remove the garden hose, and set your valve to “filter.”
DE Filters
To clean a DE filter, you can clean it like a cartridge filter or backwash it like a sand filter. If you clean similar to the cartridge filter, you will need to wash the grids to get rid of dirt and buildup. This also includes replacing your old DE powder with new power.
Ruben has a diverse background in the home services industry, with experience running a construction company, a kitchen and bath showroom, and a moving and relocation company. This breadth of experience has provided him with a wealth of knowledge and expertise in various areas of home improvement in general and specifically in the heating and plumbing niche.