The Ultra is considered by many to be the finest domestic water filter
of it's kind in the world today. Also called a hollow membrane filter
this filter is the same size filter that is used in kidney dialysis. It
is the finest (smallest micron at .01M) domestic filter available and
will remove virtually everything except for the essential alkalizing
minerals. Bacteria, Fungi and Viruses. The granular activated carbon
medium in the both filters is of highest quality that comes from the UK
and is NSF certified. Silver is also impregnated into the carbon to
make sure that bacteria do not grow there. Because it is embedded, or
impregnated, into the carbon so that silver does not leach into the
water. Tests done show that no silver is released from these ionizer
filters. Typically, if on city water we recommend the Biostone Plus
however for certain well, problem water and where there is
hyper-allergy issues we recommend the .01M Ultra filter.