.1M Aquarius Filter   [more info]	$69
	.01M Aquarius Ultra   [more info]	$89

What's the difference?
While the BioStone Plus filter is usually all the filtering you would need for typical city-supplied municipal tap water, for those who have well-water, with live bacteria and compounds not usually associated with municipally treated water, you will probably want the extra filtering capability of the .01M (1/100th of a micron) ultra filter.  This is the same filtering capacity as a typical kidney dialysis machine (woah!).  The choice is yours... but, there's no need to spend the extra money unless you really need that extra filtering capability.

more about our Biostone Filters