Abstract: The invention relates to a two-stage design for a water purification system, with water to be purified first passing through a first stage containing particulate filtration media, and a second stage containing a porous filtration block. The particulate filtration media can be the same as, or different from, material included in the porous block. Either material may be any material that removes contaminants from water by, e.g., absorption, adsorption, ion exchange, sequestration, or other mechanism, or any combination of these.

Abstract: The invention relates to filtration media having nanocrystals of metal oxides, such as zinc oxide or titanium oxide or mixtures thereof, encapsulated in or impregnated into a binder matrix.

Abstract: The invention relates to methods and compositions for reducing the growth of microorganisms and other contaminants of water processing and holding systems. Rapid reduction in the growth of fungi, algae, spores, molds, bacteria, protozoa and/or other contaminating microorganisms found in water processing and holding equipment is achieved by placing a material comprising an antimicrobial composition, preferably one containing a metal oxide and a binder, in an area of such equipment where there is water movement or storage, thereby destroying contaminating water-borne or air borne microorganisms in the water and on the surfaces of the equipment in contact with the water.