The FilterLogic HM600 is a dealkalisation filter designed specifically to remove heavy metals from the water supply. It fits inside a standard 10" housing (Ametek/Pentek style) and for drinking water applications should last approximately 3 months under regular domestic usage.
Whilst this cartridge will remove the scum and scale associated with hard water (caused by Calcium and Magnesium ions in the water) it should always have a post-filter installed which is carbon based.
This filter is typically used for drinking water, however, it is also used by aquarium owners and other hobbyists. Please note that like with all ion-exchange filters, this filter will create a proportional PH drop depending on how 'hard' the influent water is.