What’s the difference between a Sand Filter and a D.E. Filter?

Flohr Pools

What’s the difference between a Sand Filter and a D.E. Filter?

Filtration is one of the most important factors in keeping your pool water clean and clear. By running your filter, you are circulating water, chemicals, and even helping your pool water stabilize its temperature. There are many different types of filters for your pool, but two of the most common are DE filters and Sand filters. Let’s take a look at the two styles of filters and discuss the differences. The main difference, and maybe most obvious is the media used to filter the water. Sand filters use sand (No. ½ Silica Sand) to filter the water and pull debris from the pool. This is not common sand, so avoid filling the filter with sand from the backyard sandbox. Most sand filters require 50lbs up to 300lbs of sand, dependent on the filter size. Once filled, the sand can last 2-4 years. DE Filters use a combination of DE powder, also known as Diatomaceous Earth, and sometimes referred to as “dirt”. Water is filtered through the media, DE, which is “sedimentary rock composed of chemically inert, fossilized (or skeletal) remains of billions of microscopic organisms, called diatoms. Typically, pool owners add 4 – 6 lbs. of DE to the pool filter. The DE coats either a cartridge, fingers, or panels inside the filter. Water passes through the DE and filter and debris is pulled from the pool. DE needs replaced several times per season, but this varies with pool location, and how well you balance your chemicals. The filtration is also impacted by the size of the media. Grains of sand are larger than grains of DE; therefore, DE is able to filter at a much finer level. Sand filters filter water particles down to 30 microns, while DE can filter particles down to 1-2 microns. Even if you have no clue what a micron is, you can see that a DE filter will pull more debris from the pool water than a sand filter can. A final difference between a sand filter and a DE filter is the maintenance. For most owners, sand only needs replaced every 2-3 years. This means that the only regular task a sand filter requires is backwashing when the pressure rises. (Backwashing is the process of washing out the debris from the inside of the filter). This is easily done by adjusting the multiport lever to backwash, and allowing your pump to pump water and debris out of the filter for a minute. For a DE filter, the process is a little more time consuming. Filling the DE filter with DE is a process called “charging” the filter. Once the filter is charged, it begins filtering, and debris is caught by the DE. When the filter fills, and the pressure rises, the DE must be drained from the filter and replaced with another “charge”. Though this is not a difficult task, it is a little more time consuming than a simple sand backwashing, and the DE needs replaced more often than sand. Both DE filters and Sand filters are great options for excellent filtration and circulation of your pool water. The styles and sizes, as well as prices for each vary dependent on the size of your pool, so talking to a dedicated salesman would be extremely helpful in guiding your decision of the right filtering system for you and your pool.

Posted by Mark Flohr