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How to Change the Sand in Your Swimming Pool Filter

Here’s Everything You Need To Know

Pool filtering doesn’t need to be an expensive and time-consuming chore. You can use a sand pool filter to efficiently clean your pool water without needing to do much maintenance work yourself. The great thing about sand pool filters is they hardly ever clog. They’ll just keep cleaning your pool water while you enjoy the results. Just remember to replace the sand in the filter every couple of years.
There are different types of sand you can choose for your filter. Once you’ve chosen a sand type, you must find out how often you’re supposed to change it. Then you can avoid dealing with cloudy water in the future. You simply change the sand and watch as your water stays clean.

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About Pool Filter Sand

Pool filters trap so many different contaminants, such as algae, dead bugs, and bacteria. If it weren’t for pool filters, your water would be cloudy and messy. What swimmer would want to swim in such water?
Anyway, there are a certain media in the filter which grabs hold of the debris and contaminants in the water. This media is “sand,” and it works great for filtration purposes. A lot of water safety filtration systems use sand, including septic systems, drinking water systems, and wastewater systems.
The average layperson might think that all sand looks the same. They don’t realize there are different types of sands available. You can’t just purchase a bag of inexpensive play sand and use that in your filter. If you do, your filtration system will get ruined.
There are three specific types of sand which are compatible with pool filtration systems. They are as follows:

1) Silica Sand

#20 Silica Sand is the most popular type of sand used in pool filters. It is made from something called ground quartz. This type of sand contains silica grains which have sharp jagged edges. These edges are suitable for catching particles that are in the water.
Silica sand is also natural because it comes from mining. It is not manufactured like a lot of cheaper sands on the market.

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2) Glass Sand

Glass sand is the next best alternative sand media for your pool filter. It doesn’t have much impact on the environment either because it is totally made from recycled glass. And yet, the sand feels just as smooth on your fingers as regular sand. But when the glass sand encounters small particles in the water, it’ll capture them quickly. In fact, glass sand can grab onto particles which are only two microns in size. That is about one-millionth of a single meter.
There are several different sizes available for the glass grains of the sand. There is virtually no chance of channeling either. Channeling, of course, is when contaminated water passes directly through the filter sands and back into the pool without getting properly filtered. Due to the negative charge of the glass sand, it does a better job of grabbing particles made of manganese and iron from the water. If you have hard water in your pool, then you’ll appreciate glass sand filtration even more.

3) Zeolite Sand

Zeolite sand is made from a particular volcanic rock mineral by the same name. It can cover 100 times more of the pool surface than a regular sand filter. The sands are very spongey and shaped like a honeycomb, allowing it to trap more particles. It can even trap certain chlorine byproducts called chloramines, which are what cause your eyes to sting in chlorinated water. These chloramines are not killed by the zeolite sand particles. Instead, the chloramines just stay trapped in the particles for an indefinite period.
If an abundance of chloramines is forcing you to shock your pool water regularly, then zeolite sands are the best thing for your filter. You won’t even need to use as many chemical additives either.

The Importance of Changing the Sand of Your Pool Filter

The contaminated pool water is pulled into the filtration system by the pool pump. As water flows through the filter, the sand traps the contaminants in the water. This allows only clean water to leave the filter because the contaminants are stuck in the filter sand.
Thanks to the rough and edgy surfaces of the sand, it doesn’t take much for the contaminants to get trapped. You cannot see the edges with your naked eye, but they are there.
Unfortunately, these rough and edgy surfaces don’t last forever. As the sand wears down over time, its surface will eventually become round and smooth. Then it won’t be able to trap contaminants anymore. The same thing happens to sand on the beach after getting hit by aggressive waves all day long. This sand becomes softer and smoother to the touch.
The process of sand smoothing out is known as weathering. Once this happens to pool filter sand, its jagged edges are gone. If you don’t replace the sand, your pool water will quickly become cloudy. You’ll be forced to shock the water more frequently until you replace the filter sand.

Best Time to Replace Filter Sand

Pool filter sand has a short lifespan, but not as short as you might think. Your filter sand could last between 3 and five years before it needs to be replaced. Within that time, contaminants accumulate in the sand. This is actually a positive thing during the first few years because it makes it easier for the sand to pile up the contaminants on top of each other and prevent them from reentering the pool.
However, the contamination buildup on the filter sand will eventually clog the filter. On top of that, weathering smooths out the edges of the sand and makes them unable to gather any additional contaminants. As a result, the contaminants stay in your pool water and cause problems for the swimmers in it. You can’t have all that pressure inside your filter and expect it to clean the water because that won’t happen.

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Sand Filter Maintenance

Since the sand in the filter stays good for 3 to 5 years, you don’t need to replace it whenever there are problems with the filtration process. Look at the pressure gauge and see if it is at ten psi (pounds per square inch) or higher. If it is, then your sand filter needs to be back washed. You should also backwash the filter if you notice any cloudiness in the water, despite the water chemistry being balanced.
Backwashing is when the sand is rinsed, and debris is flushed out of it. Make this task a normal part of your pool maintenance routine. Then, about once every year, you should clean your sand more thoroughly with a specially formulated sand filter cleaner. This cleaner is like a sand degreaser which removes extra contaminants and oils that were not removed from the backwashing process.
If you backwash regularly and administer the filter cleaner once per year, then your water will have more clarity and better climbing pressure. These actions may allow your sand to last for five years. Once you notice the water clarity and climbing pressure diminish, that means it is time to replace the sand.

Sand Replacement

If you know your filter is causing the cloudiness in your pool water, then get ready to change the sand. It is an easy process that requires a few simple steps.

1) Deactivate the Water Pump and Filter

Deactivate your water pump and filtration system. Make sure the automatic timer is turned off or else the pump might turn on preemptively. If the pump is dry and turns on, then it will probably burn itself out.

2) Drain the Filter

The bottom surface of the filter tank has a drain plug. Remove the plug to drain the water out of the tank. This process might take some time, so be ready for that. Some people will do a little draining in the morning and then some more at night after it’s cooled off outside.

3) Take Out the Multiport Valve

Disconnect the pipes or hoses from the multiport valve. In some cases, the valve might be integrated into the PVC pipe. If that’s the case, cut the pipe if you feel like you can do so. Otherwise, hire a professional plumber to do it.
No matter how the pipe is cut, just make sure that union fittings are installed before you connect the valve again. These fittings allow you to just unscrew the pipe rather than needing to use a hacksaw.
A clamp keeps the valve secured to the filter tank. A screwdriver is needed to take off this clamp, so use one. To remove the multiport valve after the clamp is removed, slowly twist on the valve and then pull upward.
Be aware of the laterals coming out of the pipe. They branch out of there as if they’re tree roots. Between the twisting and the sand’s weight, these laterals could break easily. So, be careful.

4) Cover the Pipe

You’ll find an open standpipe inside of the tank. Use duct tape to cover the open pipe in order to prevent sand entry. Whenever sand gets into this pipe, it’ll flow into the pool water after the pump is activated. You won’t want this to happen.

5) Sand Removal

The existing sand can be extracted with a Shop-Vac device. Alternatively, use a plastic cup to scoop out the sand manually if you don’t have the device. This may take a long time, though. It is more time-efficient to use a Shop-Vac, even if you need to borrow or purchase one. The Shop-Vac is a necessity that can be used for several other pool maintenance tasks too.

6) Tank Rinsing

Once the sand is all removed, take a garden hose and rinse the drain hole of any sand particles that may still be there in the standpipe. A flashlight can help you see inside the pipe better during your inspection. If there are any cracks, then repair them first, or else sand could seep through the cracks and get into your pool.

7) Add Water to the Tank

The drain plug goes into the tank. Put the garden hose in the tank and begin adding water to it. Keep the laterals and standpipe centered, even if you need to hold them in the proper position. Remove the hose when the tank gets filled 50% of the way.

8) Add Fresh Sand

Apply a mask to your face to prevent dust inhalation. Inspect the standpipe and see if it needs more duct tape. If it does need more, then put more on.
Grab the bag of sand and slice open the corner of the bag with a utility knife. Slowly pour the sand straight into the tank. Make sure the sand doesn’t spill out. You must maintain control of the pouring so that you know where the sand is going. One entire bag of sand should be enough for the tank.
Make sure you’re using pool filter sand because it is designed for pool filters. Any other type of sand could damage the filter. Also, if you add a couple of cups of D.E. powder to the fresh sand, it’ll make the sand’s filtering abilities more efficient.

9) Add Water to the Tank

After you’ve added sand to the tank, use the garden hose to fill it up completely with water. You can now replace the hoses, pipes, multiport valve, and collar.

10) Backwash

Connect the backwash hose and activate the multiport valve. Get the pump ready and activate that. It’ll take a minimum of 2 minutes for the filter to be back washed. Any extra dust and debris in the fresh sand will be washed away from this.
Turn off the pump. Go to the multiport valve and set it to rinse. Turn on the pump. Keep the filter rinsed for 1 minute.

11) Activate the Filter

Deactivate the pump. Go to the multiport valve and set it to filter. Turn on the pump. Look at the pressure gauge and write down the reading. This is the normal amount of pressure for the pump. Any time you do pool maintenance in the future, look at the gauge to see the pressure. If it is ever ten psi more than the normal pressure reading, then the filter must be backwashed. The gauge is meant to prevent you from backwashing too much or removing too much dirt from the sand filter.


Choosing the best sand for your pool filter will be the most difficult thing here. If you make the wrong choice, it is no big deal. You can always learn by trial and error until you learn which sand is best for your pool filter.

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