biOrb Airstone

The biOrb Airstone fits in the base of the biOrb underneath the filter cartridge. It also reduces noise from the air pump. Over time the tiny pores in the air stone can become blocked by dirt and limescale preventing air from getting through properly. Depending on your local water supply and the conditions in your biOrb an air stone can last anywhere from 3 months to 3 years. Replacing the air stone every few months Small and compact