Abstract: A water purifier includes a housing that contains a purification material for purifying the water. The water purifier is placed a flow of circulating water in the spa. The purification material preferably can be a silver-containing material.

Abstract: A method of purifying water includes contacting water containing an oxide of chlorine, such as chlorine dioxide, chlorite, or chlorate, with a water purification composition that includes a Group 11 or Group 12 metal such as silver, copper, or zinc.

Abstract: A flow-through water purification method and device, the device having an inlet, an outlet, first and second internal chambers, and water purification materials in the two chambers. In one aspect, water flowing through the first chamber does not flow through the second chamber, and water flowing through the second chamber does not flow through the first chamber. The water purification material in the first chamber is restricted from contacting the water purification material in the second chamber. In a preferred embodiment the two materials are a silver-containing material and an oxidizing material such as chlorine, the device being used to treat pool water. Flow regulation means in the form of selectable output orifice areas are disclosed.

Abstract: A water-purifying device has both a strainer and water purification materials, as well as an inlet and outlet. In the preferred embodiment, the water purification materials are contained within a separable purifier housing, and a deflector extending from a support plate into a strainer housing deflects incoming water to the purification materials. The device has particular application to claimed methods of purifying water for swimming pools, spas, cooling towers, fountains and the like. The purifier housing may be an attachment to existing pump inlet strainer basket housings.

Abstract: A water purifier includes a housing that contains a purification material for purifying the water. The water purifier is placed a flow of circulating water in the spa. The purification material preferably can be a silver-containing material.

Abstract: The invention features a water purifier for purifying water in a pool having a volume less than about 13,500 gallons. In general, the water purifier has a threaded fitting that allows it to be removably-attached to a water-exchange fitting, preferably on the side of the pool. The water purifier contains a purification material for purifying the water. The purification material preferably can be a silver-containing material.

Abstract: A water purifier for killing bacteria in water located in a confined area includes a water inlet, a water outlet, and a purification unit that kills the bacteria in the water. A first fluid path is located between the water inlet and the water outlet so that water flowing along the first fluid path flows from the water inlet to the water outlet without passing through the purification unit, and includes a constricted region that has a cross sectional area that is smaller than a cross sectional area of the water inlet. A second fluid path is located between the water inlet and the water outlet, and includes the purification unit, so that water flowing along the second fluid path flows through the purification unit as the water flows from the water inlet to the water outlet.

Abstract: A method of treating water to kill bacteria therein includes exposing the water to a silver catalyst in the presence of oxygen to form an active oxidizer in the water. The silver catalyst includes elemental silver deposited on a high surface area alumina matrix. In one form of the method the active oxidizer formed is predominantly hydrogen peroxide, whereas in a second form of the method an oxidizable salt is added to the water so that the active oxidizer formed is predominantly oxidized ions of the salt. The method can be effectively carried out by adding oxygen in the form of O.sub.2 ozone to the water prior to exposing it to the catalyst.