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Sand Filter Not Cleaning

Why Is My Sand Filter Not Cleaning My Pool?

If you’re noticing that your sand filter isn’t cleaning your pool as effectively as it used to, you’re not alone. This is a common issue that many pool owners face. In this blog post, we’ll explore the top reasons why a sand filter might not be cleaning properly – and how to fix it. Keep reading for more information!

What is a pool sand filter?

A pool sand filter is a type of filtration system that uses sand to remove dirt and debris from your pool water. Sand filters are usually located outside of the pool, and they work by drawing water into the filter and then trapping contaminants in the sand.

Top reasons a sand filter not cleaning properly

There are several reasons why a sand filter might not be cleaning your pool effectively. Here are some of the most common issues:

– The sand is old and needs to be replaced.

Sand in a filter lasts for about five years before it needs to be replaced. If your sand filter is more than five years old, it’s probably time for new sand media.

– There’s too much debris in the pool.

If there’s a lot of debris in your pool, it can overwhelm the sand filter and cause it not to work properly. Try vacuuming your pool more frequently to help reduce the amount of debris.

– The valve is set to “backwash.”

The valve on a sand filter controls the flow of water through the system. If the valve is set to “backwash,” water will flow backward through the filter and won’t clean the pool effectively. Make sure the valve is set to “filter” instead.

– The sand is clogged.

Over time, sand can become clogged with dirt and debris. This can reduce the efficiency of the filter and cause it not to work properly. To clean a clogged sand filter, backwash the system and then add fresh sand.

How to know if my sand filter is working properly

There are a few signs that you can look for to see if your sand filter is working properly:

– The water in your pool is clear.

Clear water is obviously the best sign that all is working well. If your water is cloudy or has a lot of debris, it’s likely that the sand filter isn’t doing its job.

– The pressure gauge is reading normal.

If the pressure gauge on your sand filter is reading higher than normal, it could be an indication that the system isn’t working properly. Take a look at the other signs on this list to see if there might be another issue causing the high-pressure reading.

– There’s no sand in the pool.

If you’re noticing sand in your pool, it means that the sand filter isn’t trapping all of the contaminants. This can lead to cloudy water and other problems.

Professional maintenance for a sand filter not cleaning

If you’re having trouble getting your sand filter to work properly, it’s always a good idea to consult with a professional. They can help you diagnose the problem and find the best solution.

Your sand filter should be checked out by a professional at least once a year to make sure it’s in good working condition.

Other factors and solutions

In addition to the issues we’ve already mentioned, there are a few other factors that can contribute to a sand filter not working properly:

– The pool is too big/ the system is too small.

If your pool is very large, the sand filter might not be able to effectively clean all of the water. In this case, you might need to add another filtration system, such as an ozone generator or UV light system.

– There’s a problem with the pump.

If the pump isn’t working properly, it can cause the sand filter to not work properly. This is usually due to clogged impellers or bad bearings. Consult with a professional to see if this might be the problem.

– The sand is too fine.

If the sand in your filter is too fine, it can actually pass through the system and end up in your pool. This can cause cloudy water and other problems. To avoid this, use between 0.3 mm and 0.5 mm sand in your sand filter.

– Incorrect sand media.

If you’re using the wrong type of sand in your filter, it can cause problems. Make sure you’re using pool-grade sand that’s specifically designed for use in sand filters.


There are a few things you can do to make sure your sand filter is working properly:

– Check the age of the sand and replace it every five years.

– Vacuum your pool more frequently to reduce debris.

– Set the valve to “filter” instead of “backwash.”

– Clean a clogged sand filter by backwashing and adding fresh sand.

Don’t forget – if you have any questions about pool care or maintenance in the Atlanta area, our team at The Pool Butler is always happy to help! Give us a call or send us an email anytime. Thanks for reading!

The Pool Butler