Abstract: A hydrotherapeutic aerator assembly for mixing air as fine bubbles into a stream of pressurized water has a swivelable ball mating with a housing and utilizes a one-piece annular seal and retaining member with an elastically pliant lip formed on the interior diameter thereof which is attachable to the housing and engages the ball to seal and retain the ball in selectively adjusted positions.

Abstract: A one-way flow check valve is placed over an air inlet conduit to a hydrotherapy unit to prevent back flows of air and water up through and out of the conduit when the hydrotherapy nozzle outlet is blocked. A body of the valve contains a vertically-movable float which normally rests upon a retainer ring in a downward, air suction position. The float is raised upwardly and against a valve seat upon reverse flow of air and water. The light weight, buoyant construction of the float, as a hollow plastic member with top and side walls, allows the valve to shut off reverse flows of water whether fast or slow moving and to respond also to fast reverse flows of air ahead of a rising column of water. A retainer ring with float abutment pins retains the float in the body removably for cleaning the valve surfaces.

Abstract: A cartridge filter unit particularly adapted for use in a swimming pool water purification system because of its modular design, includes a readily accessible filter body. By removing a cover, a core assembly including a solids entrapping device and an inexpensive, disposable filter cartridge contained therein may be easily withdrawn for cleaning or replacement without allowing solid pollutants collected by the filter to re-enter the system.

Abstract: A hydrotherapeutic aerator assembly for mixing air as fine bubbles into the center of a stream of pressurized water has a swivelable ball carrying a nozzle in which mixing of air and water occurs before ejection of the stream into a pool or bath. A housing containing the ball and nozzle has half of a ball socket formed therein. A one-piece ball seal and retaining member attachable to the housing forms a second half of the ball socket. The nozzle is adjustable axially within the ball on cooperating threads and is made non-removable from the ball by a radially-extending O-ring snapped into a channel in a rearward part of the nozzle. A circumferential abutment surface in the ball prevents withdrawal of the nozzle beyond a selected position.