Assertion: filter | /r/CapableOf | use sand
Facets:
value: as the filtering medium
type: MANNER
Source sentences:
text: These filters use sand as the filtering medium.
text: Other filters utilizing higher-density media such as sand, foam and peat moss do not produce a sludge that must be removed, but require forced air blowers and backwashing or an enclosed anaerobic environment.[citation needed]