Below we cover the types of pool filters, how they work, as well as the pros and cons associated with each. This article also covers all the questions you may have regarding swimming pool filter types.
But before you choose the right pool filter for you, let’s find out what exactly an above-ground pool filter is.
What is an Above-Ground Pool Filter?
All pool filters function with the goal to remove debris from your pool, but above-ground pool filters are specialized for their task.
They differ from inground pool filters due to being smaller and typically not needing to produce as much water flow.
Inground filters have to transport gallons and gallons of water several feet, whereas above-ground filters have the bonus of usually being right next to the pool and being at a lower level than the pool, allowing the pump to work with gravity instead of against it.
1. Sand Filters
A sand filter isn’t named as such because it removes sand from your pool, but rather because it uses sand as a water filter.
The water enters the tank from the top and travels through the filtration layers until it is pumped back into your above-ground pool through the pool jets. This is effective for most particles larger than 20 microns and is definitely effective for most visible debris.
Sand filters require backwashing once per week during swimming season, which is a fairly hassle-free process. This is the only maintenance you will have to perform regularly.
They also require sand replacement every three to seven years.
Relatively Inexpensive Initial Cost
A sand filter starts at around $200, making it significantly cheaper than most pool filtration systems. It is also fairly easy to install and does not require professional help.
Maintenance costs are at their highest every 5 to 8 years when it’s time for sand replacement, as this usually costs around $300, labor included.
Water and electricity costs are the only factors you’ll have to budget for in between replacements, as backwashing the sand filter requires extra energy and can lower water levels a bit.
Other Filters Remove Smaller Particles
Sand filters may be sufficient for most pool owners, but it’s worth noting that it’s not the best filtration device you’ll find. Sand filters allow only particles on the larger side to go through, unlike cartridge and diatomaceous earth filters.
Backwashing Lowers Water Levels
Backwashing, while a simple process, can cost you between 200 and 300 gallons of after per backwash. This makes it quite an undesirable process, despite how necessary it is.
2. Cartridge Filters
A cartridge filter is similar to a sand filter in that it also sifts the water through a substance to clear it of debris, algae, and certain bacteria. Cartridge filters use a polyester material instead of sand.
Cartridge filters don’t require backwashing, which makes them a more eco-friendly alternative to other pool filters as it saves water and energy.
No Backwashing Required
While backwashing is a simple process, it is still something that must be remembered and performed on a weekly basis. Cartridge filters eliminate the need for this completely, saving you water, power, and labor.
Removes Very Small Particles
The average cartridge filter can filter particles of 5 microns and up.
This is quite a bit more impressive than sand filters and provides complete peace of mind to pool owners.
While above-ground cartridge filters don’t necessarily require professional installation, their initial costs are still quite high, with filters starting at around $250 and reaching around $1800.
Above-ground pools will typically only require filters in the lower price ranges, but it’s dependent on your pool size and requirements.
Requires a Bit of Maintenance
Cartridge filters need cartridge replacements every 3 to 5 years, which is more often than sand filters need sand replacements. These cartridges are a bit cheaper than sand replacement, though, as they usually come in packs of up to 4 for around $200.
In order to extend the lifespan of your cartridges, they need to be manually cleaned every few weeks by removing the cartridge and cleaning out debris.
3. Diatomaceous Earth Filters
Diatomaceous earth (DE) filters clean your pool water by filtering it through grids covered in DE powder. This powder acts as an absorbent substance in the DE filter that collects most debris, algae, and bacteria from your water before pumping it back into the pool.
Ultimate Cleaning Ability
No filtration system can cleanse your pool water quite like a DE filter system. After DE filtration, your pool water will be left drinkable.
This is because most DE systems filter particles as small as 3 microns. This is around the size of the average invisible dust particle, so you know you’re getting value for money with this type of system.
Components Rarely Need Replacement
DE filtration grids last much longer than cartridges or sand filters. This lowers maintenance costs compared to other systems in the long run.
The grids are also relatively inexpensive, ranging from $50 to $200, depending on the type of filtration system you have.
Requires a Bit of Maintenance
Compared to sand filters, DE filters require less frequent backwashing, with it only being necessary once a month, even in swimming season.
It is also necessary to clean the grids at least once per season though. After each backwashing and grid clean, DE powder will need to be added to the grids again.
Very Expensive Setup
DE filter unit prices are quite exorbitant, costing between $500 and $2000 per unit. This makes DE filtration systems the most expensive filtration systems on the market.
Which Above-Ground Pool Filter is Best For You?
All the filters covered here today have specific pros that help them cater to certain types of users.
If you are a complete germaphobe who never trusts public pools, the diatomaceous earth swimming pool filter type is the one for you, as it filters all particles larger than 3 microns. The price tag is a bit of a setback, but low maintenance costs might just make it worth it in the long run.
If you want to eliminate backwashing altogether, a cartridge filter is for you. While the cartridges do need occasional cleaning, this might still be worth it for the mid-tier price tag and top-tier cleaning ability.
If you are hoping to save money while getting decent water quality, I’d suggest a sand filter. For a comparatively low investment and only periodic maintenance costs, this option offers good value for money.
When deciding on a pool sand filter, purchase a filter that has at least 1 square foot per 10 000 gallons of water, but bigger, in this case, is also better. For instance, a 15 000 gallon pool needs at least a 1.5 square foot filter, but people often opt for a 3 square foot model, just in case.
You should have a sticker on your filter tank that can help you identify your pool filter type, but if this isn’t available you can instead look for a part number on the lateral or manifold or other internal parts, then use a site like Inyo’s Part Finder to search the component and find out what products it appears in.
Backwashing is the process of reversing the flow of water through your filter in order to clean the filter. This becomes necessary when the pressure gauge on your pump reads between 8 and 10 PSI and may increase energy usage and lower water levels.
There are three types of filters for above-ground pools, each of which has its own unique pros and cons.
The perfect filter for you depends on the money and labor you want to invest and the outcomes you are hoping for.
I hope this article has helped you make an informed decision for yourself and your family.