Carbon has long been used to absorb
impurities and is perhaps the most powerful absorbent known. Activated
carbon is carbon which has a slight electro-positive charge added to it,
making it even more attractive to chemicals and impurities. As the water
passes over the positively charged carbon surface, the negative ions of
the contaminants are drawn to the surface of the carbon granules.
Activated carbon filters are usually rated by the size of the particles
they are able to remove, measured in microns, and generally range from
50 microns (least effective) down to 0.5 microns (most effective).
The most common carbon types used in water
filtration are bituminous, wood, and coconut shell carbons. While coconut
shell carbon typically costs 20% more than the others, it is generally
regarded as the most effective of the three.
- Good filter for improving taste and odor, chemicals and some cysts.
- Bacteria can multiply in filter
- Doesn’t last long with hot water
- Doesn’t perform well at high temperatures,
needs other technologies to work as shower filter.