How To Use Sand Filters for Swimming Pools

The reason for using a filter in any application is to remove unwanted bodies from the liquid that we need filtered and cleaned. We use many types of filters in our daily chores of which some are simple whilst others could have some specialized inputs. Water being one of the most used amenities in our homes need to be filtered if we are consuming it or are likely to consume it. One of the most important filters that we use could be found attached to our swimming pools to ensure the water is completely safe to use.

Whether the pool is an above ground or in-ground, it needs a very efficient filtration system to ensure the water remains clean, clear and healthy for use. This is because an open body of water is vulnerable to many foreign bodies contaminating it. These are flying debris in the minutest form, airborne bacteria carrying multiple diseases and sickness, dust and other microscopic particles, which could cause dangerous health issues to the pool users.

An unclean swimming pool is not what we want when we decide to take a dip with our loved ones hence it is imperative that the pool is kept clean at all times. The filtration system would need to run for at least 12 hours to ensure complete filtration of the water in it. Of all the different types of swimming pool filtration systems it could be presumed that the sand filter takes the cake.

There are many advantages in using a sand filter, for one it is a naturally occurring substance, it remains as it is right through the filtration process and most of all does not have fibers of small parts that could clog the pool pump. Sand filters are also long investments with little or no regular maintenance required unlike other types of filters. Sand used in the filtration process could be used for a minimum of five years before it would need to be replaced.

To apprise ourselves about sand filters we take a look at the following which should be sufficient to convince us on the importance, relevance, practicality, usage, cost, maintenance and other salient factors to tilt our decision in favor of it. Using an efficient sand filter in your swimming pool water filtration system could be a very prudent decision and we look at why it is so.

How does Sand Filters Work?

The sand that you use in your swimming pool water filtration system is not ordinary sand which we use in other applications. “Pool sand” or “filter sand” as it is called is a specially formulated type of “#20 silica sand” which is available within the pool equipment industry. This sand is not industrial sand but uniformly coarse with standard grain sizes of between 0.30 and 0.50 millimeters.

The sand is in a special canister which passes water through it with the help of the pool pump in the filtration system. When water passes through the canister debris, dust and other foreign bodies prevalent in the water are held back or stopped from passing through. The more debris and dust that is stopped also creates a new barrier for other debris and dust which would subsequently come through. The grains of sand should be relatively uniform in size ensuring it allows water through it easily but not any debris, dust and other foreign bodies. The continuous flow of water through the sand ensures that the water passing through is clear, clean and healthy too.

Though the water is filtered it is necessary to ensure total elimination of disease carrying bacteria for which chlorine or other chemicals that are safe for humans in the right proportions are also used in the pool water filtration system. Whilst the sand filter stops debris, dust and other foreign bodies the chemicals are used kill the disease carrying bacteria making the water in the pool very safe for pool users. It is imperative that the sand filter like any other type of filter is operated prudently to derive optimum efficiency in ensuring the pool is very safe for use.

Materials Filtered by Sand

The coarse specially formulated filter sand stops a wide range of foreign bodies in the water that would flow through it. Leaves, insects, gravel, pieces of paper and any such materials are stopped by the sand filter. Foreign bodies between 20 and 100 microns are easily stopped in the first instance but some particles smaller than this size could pass through. The water filtration system in your pool is a continuous process hence particles that passed through before when they are circulated back through the sand filter continuously is stopped at some instance due to the blockage caused by the larger particles stopped in the earlier instance.

The reality is that the sand in the filter and collected debris, dust and other materials also take up the cause of filtration, ensuring the overall efficiency improves with time. Throughout the process the major advantage is that the sand in the filter remains the same without any change occurring to it either physically or chemically. It is because of this that sand has been used for centuries in the filtration of water. It is this simple principle that we use today with very effective results.

Maintenance Requirements

It is imperative that you install a pool pump with a backwash facility if you are using a sand filter in your pool’s water filtration system. This would help you to clean up your sand filter as and when required to remove the collected debris, dust and other foreign bodies. The most effective method to clean up your sand filter is to take the pressure reading in your sand filter when you turn it on the first time. Keep a note of the pressure reading in the sand filter and check on it on a regular basis. Every week would be the ideal way to ensure you are always on top of the situation until you would do otherwise.

The collection of foreign matter in the sand increases the pressure within the canister of the sand filter. The continuous filtration system collects more and more foreign matter in the sand hence the increase in pressure. When the pressure in the sand filter increases by about 8 to 10 psi (pounds per square inch) from your initial reading it would be time to clean up the sand in the filter.

Cleaning is very easy, convenient and simple. First switch off your pool pump and wait until it has completely stopped. Then attach or roll out the backwash hose in the pool pump by following the manufacturer’s instructions. Turn the pool pump’s setting to “Backwash” and then startup the pump and let it run. Initially the water being discharged will be clear but as the debris, dust and other foreign matter come the water would be dark in color. This dark colored water contains all the materials that have been collected in the sand in the filtration process. Once they are all washed out the water will clear up again then shut the pool pump down again.

Once the pool pump has stopped turn the setting to “Rinse” and then start the pool pump again and run it for about 30 to 45 seconds and then shut down the pool pump again. Next roll up or remove the backwash hose, and set the setting of the pool pump to “Filter” which is the normal setting and operate it. Keep the reading of the pressure until it increases by 8 to 10 psi and then start the above “backwash” cleaning process again. This the maintenance required when you use a sand filter, in your pool.

How to Change Pool Filter Sand

Prudent maintenance which is regular backwashing could ensure optimum efficiency in your sand filter but like everything else the sand in your filter too has a life cycle. This could be around 5 to 7 years when the sand needs changing when its efficiency drops needing more frequent backwashing. To change the sand in the sand filter is not a very difficult task but would need some patience and time depending on the quantity of sand to be replaced.

Initiate a backwash and once completed keep the pool pump switched off. Slowly open the pressure valve on top of the sand filter canister to release the pressure inside it. Then release the water inside the canister by loosening and removing the drain valve at the bottom of the sand filter. Once all the water inside the sand filter has been discharged start loosening the bolts holding the two parts of the canister together alternatively to ensure no damage occurs.

The removing of the bolts should be executed very carefully so that they are not damaged in the process as they would not have been opened for 5 to 7 years. Ensure no excessive force is applied when opening the bolts as they need to be sealed and tightened again once the sand replacement is accomplished.

Remove the top of the sand filter canister and slowly scoop out all the sand that is inside it. Once all the sand has been removed check out all the lateral components inside the canister individually. If any has been damaged or come loose ensure they are replaced and tightened again to ensure they are as good as new. This is important because you will be opening it again only in another 5 to 7 years. Once satisfied that everything is in order fill half the canister with water whilst slowly adding the new sand, this prevents any damage occurring to the lateral components. Sand should be filled within a couple of inches from the top but it would be prudent to check on the sand filter manufacturer’s instructions as the exact quantity of sand to be added.

Once the sand is in the canister and all the bolts have been firmly tightened and the sand filter is ready to operate, perform a backwash prior to restarting the filtration process again. You should have a trouble free water filtration process for another 5 to 7 years without any hassles.

Types of Sand Filters

Sand filters come in different sizes to match the different sizes of swimming pools. A small pool needs a small sand filter whilst a big pool would need a big one. It is imperative that you choose the right match which will determine the efficiency in filtration and the life expectancy of the sand filter. Over exerting a small sand filter for a large pool would not only reduce efficiency but would reduce the life of the sand filter.

It is imperative that you install the right sand filter onto your swimming pool filtration system if you are to enjoy efficient water filtration to have clear, clean and healthy water when you need to take a dip and have some fun.

• Above Ground Pool Sand Filters

Above ground pool sand filters would use gravity to bring the water in the pool into it as the sand filter and the pool will be below the water level. The water coming into the sand filter by gravity will be circulated by the pool pump. There is a slight difference in the design engineering and it would be necessary to install the appropriate one.

• In-ground Pool Sand Filters

In the case of in-ground pools the pool pump has to use suction to bring the water from the pool into the filter and push it back into the pool after the filtration process is completed. In-ground pool sand filters too have some differences in the design engineering which needs to be taken into consideration before buying the sand filter that you would install in your in-ground pool.

Sand Filters vs. Cartridge Filters:

Sand filters and cartridge filters used in the water filtration system in swimming pools do the same thing. They both trap debris, dirt, dust and other foreign bodies in the water that passes through them to ensure you have clear, clean and healthy water in the swimming pool. The difference between the two could be attributed to the initial cost between the two.

The other issues to be considered are maintenance and time consumed in accomplishing the required maintenance. To ensure optimum efficiency in operation it is imperative that proper maintenance is accorded and that too on a regular basis. Sustaining optimum efficiency at all times in comparison to the cost and maintenance would place either the sand filter or the cartridge filter ahead of the other. We could look at the two individually and make our own assessments before we could decide which of the two would be the best option to ensure our pool is kept clean, clear and healthy at all times.

Sand Filters

Sand filters employ sand in the filtration process which is a perennial practice and has been accepted as very efficient and cost effective. Though the initial cost could be slightly high there are no costs thereafter though regular backwashing is required to ensure optimum efficiency in operation. Backwashing which needs to be executed either fortnightly or every month could depend on the pools environs. If the pool is subjected to excess debris, dust, pollen, insects and other foreign bodies the frequency of backwashing could increase.

Backwashing could consume some time which is something that most of us do not have in our hands. On the contrary backwashing does not entail any cost other than the fraction of electricity used in operating the pool pump. The other aspect is the sand that is employed in the filtration process needs to be replaced over a period of either 5 or 7 years. The sand will keep good until then and with regular and timely backwashing you could have cost effective and efficient filtration of your pool water.

• Sand Filter Advantages

Initial investment only and after that other than time spent on backwashing no costs involved on a regular basis. Cost would be entailed again when the time arrives to replace the sand which will be either in 5 or 7 years. The filtration process is very effective and you will have clear, clean and healthy water to enjoy with your loved ones.

• Sand Filter Disadvantages

Regular backwashing could be quite irritating if you are a busy body and one who would have severe constraints in time. The backwashing process needs to be exercised when needed or your sand filter will drop in efficiency.

Cartridge Filters:

Cartridge filters are easy to maintain where the cartridge could be removed washed in running water and replaced again. There is no hassle and does not consume much time. The cartridge filter has a lifespan which is decided again by the environs where your pool is situated. If the pool is open to much exposure to debris, dust, insects, pollen and other foreign bodies the frequency of cleaning the filter will increase.

At a limited time the cartridge will need to be replaced which could be quite expensive because cartridge filters are not cheap and depending on the brand, model and size of the cartridge filter the cost could be high. Replacement of cartridge filters in comparison to sand in a sand filter could be quite a drain on your wallet.

• Cartridge Advantages

Time in today’s context is one of the most important and expensive “commodities” that many of us do not have in our hands. It is imperative that we attend to all our chores within a limited period of 24 hours in a day. Time cannot be bought hence we need to manage it prudently. Every minute we save could be very valuable to us.

Easy and convenient maintenance, as there is hardly any hassle. Remove the cartridge clean it under running water and replace it again. This exercise needs to be conducted regularly to ensure optimum efficiency but it does not consume time like the backwashing exercise in a sand filter.

• Cartridge Disadvantages

Cartridge replacement on a regular basis could be a very expensive exercise. Here unlike time it is a drain on our wallet. We need to replace the cartridge every time the efficiency of the filtration system comes into question. This could be higher in some areas which could place you in quite an awkward position if you are to replace cartridges regularly.