No, limescale is not filtered by British Berkefeld® systems.

The limestone found in water is mainly composed of calcite (calcium carbonate) and magnesium carbonate.

These mineral salts, in ionic form, are not filtered and pass through the filters. This provides a supply of calcium and magnesium, which is also beneficial to health.

So don't be surprised if limescale builds up on the walls of your lower tank. Even if this tends to stick less, because of the change in the ionic charge of the minerals that pass through the ceramic of the filters. This sometimes leads to the presence of small white particles suspended in the water or residues that accumulate at the bottom of the lower tank.

Don't hesitate to clean your lower tank with household vinegar diluted in warm water to remove any residual traces of limescale.