Choosing the Best Filter Media for Sand Filters

You would think sand is the best option for any sand filter, right? Well there are some factors to take into consideration when choosing a filtration media: the cost, its effectiveness, and longevity.

There are three big players in the sand filter business, and we will take a look at each of these. The three are sand (obviously), zeolite, and glass.

Sand Media

Silica sand is the oldest and most trusted media for sand filters. All sand is different, so don’t trust just any old bag of sand. Silica is definitely the way to go. If you get number 20 silica sand, that means it will filter up to 20 micron particles (much much smaller than the human eye can see). The downfall is silica will get some algae but not prevent algae outbreaks. Some algae an be 5-10 microns in size. That will require an extra clarifier to group the algae cells together in order for them to be large enough for the filter to catch them. The average silica sand filter will last 3-5 years before it will need to be replaced.

Zeolite Media

Zeolites are from volcanic rocks. They form from a reaction with ash layers and alkaline groundwater. It can also be produced in a laboratory. In a nutshell, zeolites are micro-porous and catch debris flowing through your filter. They can filter particles down to 5 microns making the filtration power much stronger than sand. This doesn’t necessarily mean zeolite is the way to go- be aware that when you put it in your filter you will create a  lot of dust. The dust will run into your pool if you do not do a thorough backwash. We recommend backwashing for at least 3-5 minutes. A bonus of zeolite is you only need about half the amount of sand. It is more expensive than silica sand but should last a year or two longer before needing replacement.

Recycled Glass Media

This option is not only environmentally friendly, but it actually works! When you recycle glass particles, some manufactures don’t like to use scrap glass because of the mis-matched coloring. This is when the glass can be taken and used for pool water filtration. Glass filtration can filter particles down to 9 microns, far more than sand. It saves water and money because it will require less backwashing. Recylced glass is known to last 10 years or longer as well. Ask the Pool Guy pros highly recommend choosing a recycled glass media option for your pool sand filter!