External filtering device for use in a local containment area for removing oil and other contaminants from storm drain effluent as it exits storm water systems; Filters for air conditioning; Purification installations for sewage; Waste water purification apparatus, installations and tanks; Water filtration and purification units and replacement cartridges and filters therefor; Water purification units; Water purification, sedimentation and filtration apparatus for clarification, thickening and filtration of water, waste water and industrial water; Water treatment apparatus, namely, clarification and thickening machines for use in treatment of liquids in the nature of water, waste water and industrial water; Water treatment equipment, namely, reverse osmosis units; Water treatment equipment, namely, water filtration units