Abstract: A cradle system used in purification systems for releasably capturing and reversibly displacing a set of cylindrically contoured filter cartridges mounted thereon. The cradle system includes at least a first longitudinally extending cradle frame having a pair of first rod members within which the filter cartridges are mounted. At least a second longitudinally extending cradle frame having a pair of longitudinally extending and transversely displaced second rod members is coupled to the first cradle frame. Coupling is provided by a cradle rotational securement mechanism which constrains the first cradle frame to the second cradle frame but allows rotational displacement of one cradle frame with respect to another.