How to change the sand in a Pool Filter

In order to properly maintain your swimming pool filtration system it is important to periodically change the sand in your pool filter.  The sand becomes so saturated with organic debris, skin, hair and oils that it is no longer able to filter the water sufficiently to maintain clarity.

The logic behind never changing your filter sand is that dirty sand actually filters better than brand new sand.  The flip side to this is that after enough time the sand will no longer be able to filter the water well enough.  From a manufacturer standpoint it is recommended that you change the sand in your filter every 3-4 years.  This will maximize the effectiveness of the filter and help you to maintain clean and clear water.

1: Remove the sand by scooping the sand out with your hand (Please use protective gloves as there is a lot of bacteria and dirt in the sand) or with a small shovel.  The sand in an old filter can actually be laden with bacteria so it would be better if you minimize your direct contact with the sand.

2: After removing the old sand you will want to add water to the tank before adding new filter sand.  This water helps to absorb any impact of the falling sand on the lateral assembly.

 3: Be sure not to get any sand into the sand pipe which will be wide open.  It is difficult to get the sand actually into the filter without getting it in the sand pipe so you may like to tape up the standpipe opening to prevent this spilled sand from making it back to the pool through the return lines.  It is also very important that the sand pipe is directly in the center of the filter as once you have filled with sand you will not be able to adjust the position of the sand pipe.  If not centred you will not be able to get the valve head back on the filter and will need to start all over again.

The type of sand that you add to the filter will be #20 silica sand which is specifically produced for filter medium.  This sand is between 0.4-0.5mm in diameter and is available from most swimming pool supply stores.  Do not substitute other types of sand or you will almost certainly have problems with your filter and potentially damage the pool also.

4: The amount of sand that you add to the filter will depend on the size of filter that you have.  You must be certain to find accurate information about how much sand to use in your filter.  Over filling or under filling the filter will cause the filter to not function properly and at worst cause damage to the filter? Sand Filters sizes range typically from 1 bag to 5 bag, each bag weighing 40kg.

5: Once full you can put the filter head back on being absolutely certain that it is tight enough.  This is where a skilled hand is helpful as if you over tighten the filter head then you may actually crack the filter body which would require replacement of the entire filter – something you definitely want to avoid.

6: Once back together the first thing you need to do is give the filter a thorough backwash.  You should start this process by over filling the pool and then backwashing for as much as 3 to 5 minutes, followed by a 60 second rinse cycle before setting to “filter”.

The above information was extracted from http://www.wikihow.com/