Water treatment devices and cartridges therefor

A water treatment cartridge for treating water, said water treatment cartridge capable of sealingly and releasably engaging a water treatment device, said water treatment cartridge comprising:

• (a) a housing, an inlet for introducing water into said water treatment cartridge, an outlet port for egress of treated water from said water treatment cartridge, and a treatment media for treating water, said treatment media being in fluid communication with said inlet and said outlet port;
• (b) a first tube comprising an inside surface, an outside surface, a proximal end, and a distal end, wherein at least one of said inside surface and said outside surface comprises a sealing surface;
• and
• (c) a second tube comprising an inside surface, an outside surface, a proximal end, and a distal end, wherein at least one of said inside surface and said outside surface comprises a sealing surface;
• wherein said first tube extends from said housing and surrounds said outlet port forming a treated water passageway;
• wherein said second tube surrounds said first tube such that a gap is formed between said first tube, said second tube, and an outer surface of said housing;
• and wherein said gap is disposed between said inlet and said outlet port;
• and wherein said second tube extends from said first tube, and said first tube extends from said water treatment cartridge housing.