Clean the sand filter

Sand filter systems are very popular because, on the one hand, they filter very efficiently. On the other hand, they are particularly low-maintenance. Although the filter medium does not have to be replaced regularly at short intervals, it has to be cleaned again and again. This guide will tell you how to clean a sand filter and what to watch out for.

The sand filter compared to cartridge filters

Especially those who still have to decide on a filter for their system often do not know whether a sand filter or a cartridge filter is better. However, cartridge filters are nothing more than paper or mat filters. After a while, they are so dirty that they have to be changed.

  • Also read - sand filters for the pond
  • Also Read - Sand Filters Or Cartridge Filters?
  • Also Read - Sand Filters For The Well

Replacing the filter medium

This is exactly where the advantage of sand filters lies. These not only filter with high efficiency, at the same time it takes a long time, even with a heavily polluted fluid, until the sand itself has to be replaced. The following data for changing the sand in the sand filter according to the intensity of the pollution:

  • conventionally polluted water: every four to five years
  • moderately polluted water: every three to four years
  • heavily polluted water: every two to two years

Renewing the filter sand is not enough

However, the type of pollution is also decisive. It may be that the replacement of the filter sand is only necessary after four or five years, even if it is very dirty. That depends on how well the sand filter can be rinsed. Because of course it is not only sufficient to renew the filter sand every few years.

In between, the sand has to be cleaned

The dirt that collects in the sand has to be removed from the sand every now and then. You need to clean the sand on a regular basis. But that is very easy. This process is called "backwashing the sand filter system" when cleaning the sand filter.

Cleaning the sand filter

Backwashing the sand filter consists of two steps. To do this, however, it is first important to know how a sand filter system works. The water to be cleaned is pumped to the multi-way valve. This is set so that the basin drain is opened and the inlet to the water distributor (located in the top of the filter housing) is opened.

The backwash

If the water were filtered conventionally, it seeps through the sand and then into the filter star. From here it is then via the drain on the multi-way valve to the water basin (pool, aquarium, pond, etc.) funded back. Now, however, the multi-way valve is set in such a way that the water is pumped into the sand filter from below via the filter star.

Dirt and water are pumped down the drain

Now it pushes the water up through the sand. From here it is then conveyed from the water distributor to the multi-way valve. All of the dirt that has accumulated during the filtering process is also pushed upwards. Instead of the inlet to the water basin, the connection to the wastewater is now open on the multi-way valve.

After backwashing, the sand filter is rinsed off

During this backwashing process, not only does dirt get into the pipe system and the multi-way valve. Sand can also settle there. Therefore, after extensive backwashing, it is now rinsed. The water is regularly pumped back into the sand filter, i.e. from above via the water distributor.

Also now is promoted to the sewage

On the multi-way valve, however, the inlet to the water basin is not open, but the one to the wastewater. The entire pipe system and the reusable valve are then cleaned of dirt and sand residues. The sand filter cleaning process is now complete and the normal circulation for filtering the water from the water basin can be restored.

Tips & Tricks Since the sand itself only needs to be changed every few years, it is easy to forget the procedure. That is why we have summarized all the important information about the filter sand under "Sand filters and sand ", including the sand height, the grain size used and what multilayer systems are all about.