There are three types of filters including Sand, Cartridge and DE (Diatomaceous Earth).
Sand Filters
Sand Filters consist of large tanks filled with sand. The water gets pushed through the sand which filters out any contaminants before they end up in your pool, thus clarifying your water. Sand filters remove particles as low as 20 microns which become caught within the grains of sand. Eventually the particles will block more and more water, raising the pressure in the filter. This will cause your filtration system to backwash or flush out the system by reversing the water throughout the filter.
Pros:
- Easy maintenance
- Cheap to replace
- Sand lasts 7 years
Cons:
- Requires backwashing (almost weekly)
- Wastes water through backwashing
- Filters down to 20-25 microns
- Creates the most pressure, making it less energy efficient
Cartridge Filter
Cartridge Filters are energy efficient, cost effective, and readily available. They consist of a filter cartridge which sits in a tank smaller than that of a sand filter and filters water through the large surface area of the filter. The cartridge’s clarity lands in the middle, filtering down to 5 microns which are picked up through the paper-like material within the cartridge. Because the filter has a large surface area it creates the least resistance and works the best under lower speeds. The cartridge filter can be taken out and sprayed down with a hose for cleaning and doesn’t require backwashing.
Pros:
- No backwashing
- Filters good at lower speeds for energy efficiency
- Greater surface area
- Traps particles as small as 5-10 microns
- Saves water
- Most Economical
Cons:
- Cartridges need to be replaced more often (every three years or so)
Have to clean the cartridges once or twice a season.
D.E. Filter
D.E. or Diatomaceous Earth Filters use mined fossilized exoskeletons of tiny diatoms to filter out particles. The D.E. Filter consists of a tank with a grids inside coated with D.E. Powder. The D.E. Powder acts like sand catching particles but on a much smaller scale. It catches particles as small as 3 microns, giving the clearest water out of the three filters, but not without a higher price. The D.E. Filters have a little pricier upkeep than Sand or Cartridge Filters, requiring you to replace D.E. Powder every time you have to backwash the filter. You can do this easily by adding D.E. Powder to your skimmer but you will have to give the filter a thorough cleaning once a year.
Pros:
- Filters particles as small as 5-10 microns
- E. can be added through your skimmer
Cons:
- Higher maintenance costs
- Costly
- E. Powder is carcinogenic in it’s powder form
- Grids need to be cleaned once a year
- Higher resistance than cartridge filters
Which is the best?
In terms of overall performance our pick goes to the Cartridge Filter. The Cartridge Filter allows for an energy efficient, cost effective system, that still provides you with clear water. It does this by having a large surface area which allows for great filtration while being able to allow pump speeds to remain low. The lower the speed, the lower the pressure and friction in the lines, thus decreasing the amount of energy consumed by your pump.