How To Change Swimming Pool Filter Sand?

The filter sand is usually changed every 1 – 3 years and, if the sand is more worn, after one year. According to the manufacturer’s instructions, after the water in the filter has been drained and all screw connections have been loosened, the sand is removed, and the filter is filled with a new filter medium.

The following equipment is required for changing the sand in a pool filter.

  • Garden glove: This is used to remove the sand.
  • Bucket: A simple bucket for the sand is sufficient.
  • Open-end wrench: This is required to loosen the screw connection of the cover.
  • Oil filter wrench: capturing the outer diffuser connector.
  • Slotted screwdriver: Can be handy to spread.

You will indeed have most of the equipment at home in the garden shed. If not, you can find the right equipment in the online shop under the links.

In this post, you will find detailed instructions on how professionals change the sand filter system’s sand. In addition, with the tips, you will learn what to look out for to avoid consequential damage to the system and problems with water treatment.

Why Change Your Pool Filter Sand?

Changing the pool filter sand is essential to maintain water clarity and hygiene, as the sand loses its effectiveness in trapping contaminants over time. The 4 main reasons for this necessary pool maintenance are listed below.

  1. Contaminant Trapping: Sand acts as a medium to trap harmful contaminants like bacteria, algae, and debris, crucial for maintaining clear and safe pool water.
  2. Surface Roughness: The effectiveness of sand in trapping these impurities is due to its initially rough surface. As water continuously flows through the sand, this roughness plays a key role in catching impurities.
  3. Weathering Effect: Over time, the sand undergoes weathering. This process smoothens the sand’s surface, reducing its ability to trap contaminants effectively.
  4. Impact on Pool Health: As the sand becomes smoother, its filtering capability declines, leading to issues like cloudy water and the need for increased chemical treatments.

Therefore, changing the pool filter sand is an essential aspect of pool maintenance. It ensures the continuous effectiveness of your pool’s filtration system, maintaining both the aesthetic clarity and the health safety of your pool water.

1. Turn Off The Pump

To ensure safety, the first step in changing the pool filter sand is to disable the power supply to the pool area. Specifically, remove the fuse for the pool system to prevent the pool pump from accidentally starting. This precaution is critical as running the pump while dry can cause damage or burnout. Additionally, verify that the pump’s timer is off to avoid any automatic activation during the maintenance process.

2. Close The Pool Valves

Once the power is safely off, close all valves of the pool system. This step is crucial to prevent water from escaping once you open the sand filter. It’s a necessary measure to maintain the integrity of the system and to avoid water waste or spillage during the sand replacement procedure.

3. Remove The Multiport Valve

The next step involves accessing the sand filter by removing the multiport valve. If your system uses hard plumbed PVC pipe, you will need to cut the pipe. Installing union fittings after cutting will facilitate easier removal in future pool maintenance. Use a screwdriver to loosen the clamp or collar securing the pool valve to the tank, then gently twist and pull up to remove the valve. Keep the gasket, lid, and diffuser in a safe place.

4. Open The Water Drain

Find the water drain at the bottom of the filter system and open it to drain out the water. Accelerate the drainage by loosening the inlet and outlet of the multiport valve and using a screwdriver to pry them apart. This step is essential for efficiently removing water from the system before proceeding to the next stage of maintenance.

5. Turn The Diffuser Connector Aside

After draining the water, loosen the screw connection to the multiport valve. Use an oil filter wrench to turn the diffuser connector to the left, while simultaneously gently pushing in the same direction with your free hand. After adjusting the connector, close the screw connections again to prevent sand from contaminating the threads.

6. Remove The Sand From The Filter

Prior to extracting the old sand, cover the nozzle with a plastic bag, securing it with rubber bands to ensure it stays in place. You can then remove the sand using garden gloves and a bucket or employ a Shop-Vac for a more efficient process. If you choose to remove the sand manually, a plastic cup can be used as a scooping tool.

7. Close Screw Connections

Following the removal of the old sand, reseal the drain screw on the sand filter system. It is also important to rinse off any sand from previously opened screw connections and close them. This step ensures that all connections are clean and secure, which is vital for the proper functioning of the filter system.

8. Fill The Sand Filter System With New Sand

Before introducing new sand, pour a liter of water into the filter. This preparation aids in the even distribution of sand and the effective positioning of the absorber arms. When refilling, adhere to the manufacturer’s specifications regarding the quantity and grain size of the sand, which should be between 0.4 and 0.8 mm. The correct filling level is typically just below the upper nozzle.

9. Concluding Work

With the new sand in place, reposition the diffuser connector and remove the protective plastic bag. Reattach the diffuser, and ensure that the cover seal, lid, and all other screw connections are thoroughly rinsed and properly secured. Care should be taken when tightening the screw connection to avoid excessive tension and potential leaks.

10. Backwash The Sand Filter

The final step is to open all valves and backwash the sand filter system. This process involves flushing out any residual dirt and ensuring the new sand is properly settled. Observe the water in the sight glass of the multivalve; backwashing the sand filter is complete when the water appears clear. Following backwashing, conduct a rinse cycle before returning the system to its regular filtration mode.

By following these detailed steps, you can effectively change the sand in your pool filter, ensuring the cleanliness and efficiency of your pool’s filtration system.

What sand To Use for Your sand filter system?

Selecting the right sand for your sand filter system is crucial for efficient pool cleaning. Different types of sand can be used in a sand filter system. The 5 main filtration options for your sand filter are listed below.

  1. Standard Filter Sand: Often referred to as Silex sand, it’s commonly used in filter systems.
  2. Filter Glass: Comprising fine glass particles, this type is noted for its eco-friendliness.
  3. Activated Carbon and Sand: This combination in multi-layer systems enhances filtration.
  4. Fibalon: A modern medium, Fibalon serves as an alternative to filter sand and glass.
  5. Diatomaceous Earth Filter: Uses DE earth, an organic material, for filtration.

It is essential to adhere to the manufacturer’s specifications regarding the type of sand suitable for your filter system. But what is the ideal grain size for filter sand?

Manufacturers generally provide specific grain size recommendations. In the absence of such information, a Silex sand with a grain size of 0.4 – 0.8 mm is typically used. The key is to balance the sand’s fineness for effective turbidity removal without it being too fine, which might hamper the system’s functionality. Regular backwash is also crucial to maintain efficiency.

How much sand goes into a sand filter system?

The quantity of sand in the filter system significantly affects water treatment. The fill level is usually indicated on the sand filter’s housing. In the absence of manufacturer instructions, the sand level should be just below the upper inlet nozzle. Incorrect sand amounts can damage PVC pipes and impair filter performance. The sand’s grain size should also be considered, with 0.4 – 0.8 mm being a common choice in the absence of specific manufacturer guidelines.

When To Change The Sand In Your Filter?

Changing the sand in your pool filter is a critical maintenance task. However, not every situation in pool maintenance requires a complete sand replacement. Situations necessitating a sand change include.

  • Sand age over one year or visible wear.
  • Persistent cloudiness despite proper water balance and flocculant use.
  • Formation of flakes on the pool floor despite flocculant use.
  • Frequent algae problems, including black algae.
  • Unusually high chlorine consumption with correct cyanuric acid levels.
  • Calcification of sand due to hard water, weakening water return flow.
  • Cloudiness during vacuuming, indicating inadequate cleaning.

Troubleshooting before changing sand can help identify the cause, but in complex cases, replacing the sand is often the most effective solution.

How often to change the sand in the sand filter?

Manufacturers might recommend annual changes, but practical experience suggests changing the sand every 1 to 3 years, depending on usage and wear. In outdoor pools, a typical interval is 2 to 4 years, while indoor pools might differ. Pay attention to signs like cloudy water, which can indicate the need for sand replacement. Backwashing can also help maintain clean pool water.

Do you have to refill the sand filter system with sand?

No, using sand in your sand filter system is not mandatory. Alternatives such as Filter Glass, Fibalon, or D.E. Filtration Sand are viable options. However, refilling the filter system with sand is the best option for swimming pool care. Backwashing can lead to a slight loss of the filtration medium. This loss is more pronounced when using DE soil, which can result in a 10 – 90% loss, or in multi-layer filter systems that incorporate activated carbon.

What To do if sand ends up in the pool after changing sand?

If sand appears in the pool post-backwashing, it could indicate a loose or broken pipe. This issue often arises from overfilling or applying excessive force during sand change. Identifying and replacing the damaged part is necessary to resolve this issue.

We recommend our blog and the search function for more guides about pool maintenance. If you have any questions about pool care, don’t hesitate to reach out to us via social media. We’re here to help you out.

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Conan Grout is a renowned pool care expert, specializing in maintaining optimal water chemistry, crucial for a healthy swimming environment. His expertise covers essential practices like regular pH, salt, and chlorine level checks, debris skimming, and algae-preventing brushing. Additionally, Grout is adept in advanced pool cleaning techniques, including the use of nonabrasive chlorine-based solutions for challenging tile scum. His comprehensive skill set makes him a trusted authority in swimming pool maintenance.