The original Athena #1 filter was a carbon filter. Carbon filters will remove more chemicals and less sediment than regular sediment filters. If you have high sediment in your water, choose the AlkaViva Athena #1 Fiber-Sediment Filter.
Change filters at least yearly.
![Supercarbon [Catalytic Carbon] Prefilter](jpg/standard-10-inch-filter__206004847.jpg "Supercarbon [Catalytic Carbon] Prefilter")