Sand VS Cartridge Filters

What is the Best Filter for a Swimming Pool?

Your pool’s filter plays a huge role in the maintenance of your pool, and is responsible for keeping your water clean, free of debris and contaminants. If you’re unaware of the way a filter works, and the kinds of pool filters available, you might have some trouble finding the correct one for your pool. The two most commonly used types of filters are Sand and Cartridge filters. These two offer different benefits, and vary significantly in how they work. In this article, we will outline the difference between these two kinds of filters so that you can have a more accurate picture of what each one can offer your pool.

Sand Pool Filters

Sand filters are generally a large, cylindrical apparatus which contains a chamber that is filled with sand or silica. High-pressure water enters from the top, pumped through your system, and is forced through the sand, making its way out the bottom. Any contaminants and debris get stuck in the sand, meaning all that can get through is clean water. As time goes on and more debris accumulates, the filter gets even more effective at removing contaminants as the holes water can go through getting smaller. Despite this, the sand filter is not fool-proof and should be used in conjunction with chemical sanitation.

Sand Filters Maintenance

The sand in your filter should be replaced once every few years on average, varying based on the amount of dirt and gunk in your pool. Usually, the filter can be easily maintained through backwashing, or a reversal of the water flow to knock out particles. As sand filters are generally the cheapest, they are also the least effective and require regular maintenance. The sand removal and replacement process is quite difficult and will often require you to call in a professional for help. They will have to be cleaned more frequently and will require more chemicals used alongside the filter as part of your regular maintenance schedule.

An excellent quality Sand Filter is the Pentair SD40 Sand Dollar. This filter’s internal design keeps the sand bed level for consistent performance and filtration, offering above average filter performance. This model is available for various operating capacities.

Cartridge Pool Filter

Another common option is the cartridge filter, which uses thin sheets of fabric to filter water. Water is pumped through the fabric and any debris and contaminants are blocked by the minute holes in the fabric’s weave. Water has to pass through many layers of this filtration, reducing the amount of debris that gets through. Of course, molecules smaller than water such as bacteria can still pass, meaning that it’s best to use a Cartridge filter in conjunction with chemicals to ensure the best hygiene.  

Cartridge Filter Benefits

Cartridge filters are generally more effective than sand filters because they can filter smaller particles and have a wider surface area, meaning more water can be filtered through them at a time. Unlike the sand filter, they don’t need backwashing to clean, and the cartridge can simply be removed and cleaned regularly. They are also easier on your pool’s pump and require less pressure to move water through. However, they have a shorter lifespan than sand filters and will need to be replaced every one or two years. They are also on average slightly more expensive.