Which Pool Filter System is Best for You?

In our last post, we talked about pool tips for beginners. This time, let’s look at the filtration system in your pool. Filters are an important part of keeping your pool sparkling and clean. Filters catch the minute debris in your pool, cleaning the water and preventing bacteria and algae from growing. The pool pump circulates the pool water and pushes it through the filter where the debris is trapped.

There are two main types of filter systems we use for in-ground pools:

Cartridge filter
DE (diatomaceous earth) filter

Cartridge Filter

A cartridge filter is the most simple of the pool filter options and can filter particles down to 8-10 microns which is sufficient for a swimming pool. The filters can easily be removed and sprayed with a garden hose or a car wash hose for cleaning. Cartridges need to be cleaned every quarter and can last for two to three years before needing to be replaced.

Because cartridge filters have a large surface area, the pool pump can work at lower speeds and still move the same volume of water through the filter, making them more energy efficient than DE filters.

Please note: If you are battling algae in your pool, you will need to clean the filter cartridge frequently until the pool is clear.

DE (Diatomaceous Earth) Filter

DE (diatomaceous earth) is a filter grid coated with DE powder, which is fossilized exoskeletons of tiny diatoms. A DE filter can filter out debris down to 3 microns. While DE filters have better filtration, they have their share of cons. Instead of simply hosing down the screen like with a cartridge filter. DE filters must be backwashed, which takes significantly more water. The runoff water from the backwash goes into a separation tank and into the house clean-out system, all of which must be set up when the DE filter is installed. Another problem with DE filters is they must be recharged after being cleaned and they need to be rebuilt yearly.

Many pool maintenance companies like DE filters because they are easily cleaned by backwashing. However, at The Complete Backyard, we feel the cartridge filters are the greener option to due to the significantly smaller volume of water which is used to clean the filter. Remember, not only does backwashing use water from your pool to clean the filter, which must then be replaced, but the chemicals in your pool must also be rebalanced after a backwash to be sure you haven’t lost too much.

Pros and Cons of each Filter

Cartridge Filter Pros:

Filter cartridges have cheaper upfront costs
Cartridge filters are also more environmentally friendly due to less water being needed to clean the filter
Even though a cartridge filter does not capture particles as small as a DE filter, they are still more than sufficient to keep a pool sparkling clean.

Cartridge Filter Cons:

A cartridge filter takes about thirty minutes to breakdown and clean
A cleaning service call for a filter cartridge will cost more due to the length of time it takes to clean the cartridge

DE Filter Pros

It only takes 10 minutes to backwash and clean a DE filter
DE filters can capture smaller particles than a traditional cartridge filter

DE Cons

The cost of water to backwash a DE filter can really add up
Some cities have banned the use of DE filters due to the volume of water required to backwash and clean the filter
DE filters need a complete breakdown once each year

Sand Filters

You may have noticed we haven’t mentioned sand filters. Sand filters do not compare to either cartridge filters or DE filters. They do not provide the same level of filtration, meaning your pool is more likely to look cloudy with a sand filter than either of the other two options. Another drawback to sand filters is they need to be backwashed, just like a DE filter, causing significant water and pool chemical waste. Due to these two concerns, we do not recommend homeowners install a sand filter on their pool.

Other Filter Thoughts…

At The Complete Backyard, we like to oversize the filter for the pool. For some homeowners, we might even recommend a pool to be built with two filters if they have several extra features such as a spa, waterfalls, fountains, water slide, etc. There are many advantages to the homeowner in doing this. If the filter is oversized for the pool, there is more surface area to catch debris as it is being pumped through the filter. The filter can go longer between cleanings, leaving less work for the homeowner.

As with many things in life, homeowner personal preference in pool filtration is important. Homeowners should take into account not only the initial installation cost of the filter system but also the cost of the lifetime maintenance of the different filters. They need to weigh the pros and cons of each filter type and add up the cost of replacement parts and service calls. They should consider their comfort level with the routine maintenance of each filter type before making a final decision.