Pool Sand Filter Maintenance

Pool sand filter maintenance is actually quite easy and can be done by most pool owners.  It will take just a bit of time and effort and you'll be back to having a sparkling clean salt water pool in no time. 

pool sand filter maintenance

A sand pool filter will allow you to spend more time enjoying your pool and less time maintaining it.  They are easy to backwash and sand is relatively inexpensive, especially considering how infrequently it needs to be replaced. The most common form of maintenance you will perform with your sand filter is a backwash.  The average sand filter will need to be backwashed once every week or two but that depends on usage.

Every 3 - 5 years as an average you will need to change the sand to ensure it is cleansing your pool effectively.  If the water is cloudy, and not related to water chemistry, it might indicate the sand needs to be changed. As the sand ages it loses its ability to clean effectively.  The tiny grains of sand lose their rough edges and become rounded.  As they round they lose their ability to trap debris and other fine particles. The sand can also clump or calcify which creates channels where the water passes through unfiltered. 

Pool Sand Filter Maintenance Step by Step

A sand filter is a great option for salt water pool owners for several reasons. The downside is they need to be backwashed regularly but the good news is that backwashing is quite easy to do.  A general rule is to backwash when the pressure rises 6-8 lbs above normal operating pressure.  Pool sand filter maintenance is simple and the benefits of a sand filter make it worth the time. 

Sand Filter Backwash Instructions

Follow these simple steps to ensure your pool runs smoothly. 

  1. Empty the skimmer of debris, leaves, etc. as they will get sucked and trapped in the filter and forced back into the pool.
  2. Turn the pump off and empty the basket of debris.
  3. Ensure that the "cut-off" valve is open if necessary.
  4. Switch the backwash valve to "backwash" and turn on the pump. Run the pump until the water runs clear that can be seen in the sight glass.
  5. If the filter does not have a plunger valve switch to "rinse" and run until water runs clear.
  6. Turn the pump off and switch to "filter" position. 
  7. Turn the pump back on. 

The sand in your filter should be changed every 2 years on heavily used pools and 5 years on less frequently used pools. If the pool is cloudy and is not related to chemistry it may need early changing.

Changing Filter Sand

If you need to change the sand refer to your owners manual for instructions on how to open your filter.  Replace with the appropriate amount of pool filter sand depending the size of your filter.  If you are unsure you can fill your filter tank 2/3 full of sand as a rough estimate.

  1. Remove the sand either by scooping it out or using a shop vac. It's important to get as much of the old sand out as possible.
  2. Check for signs of damage or cracks that could be compromising the effectiveness of your filter.
  3. Cover the standpipe with a cloth or rag to prevent any sand from getting in during your thorough cleaning.
  4. Fill the tank with sand just above the laterals and then follow with filling sand up to cover the laterals.
  5. Lube the tank o-ring and all other o-rings with a teflon based lubricant or sealant.
  6. After closing the tank, backwash for about 5 minutes and then set valve to "filter" position.

If you use water softening chemicals there is the possibility that the life of your sand will be reduced.  Keep this in mind if you choose to use these chemicals. If you are using a salt water system, water softening chemicals won't be required to achieve soft silky water!

If you find that sand isn't meeting your filter expectations you might consider adding a small amount of DE (diatomaceous earth) to your sand or consider using zeosand instead of sand.  Zeosand can be used with all makes and models of sand filter with no modifications.  There are a few advantages that zeolite filter media has over sand including improved filtration.

Pool sand filter maintenance is the quickest and most straight forward maintenance you'll perform on any of the available filtration systems.  The quality of filtration isn't as superior as a DE or cartridge filter but for the pool owner that wants to spend more time swimming and less time maintaining his pool, this could be the right choice.


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