The Kidney Loop with Change-Over (KLCO) system is a stationary off-line fluid conditioning system for removing solid particle and free water contamination. The KLCO features an RLD (25DN or 40DN sizes) series duplex-type filter, allowing users to change the direction of flow through one of two filters, and the ability to replace filter elements without shutting the system down. This is particularly beneficial in fluid conditioning applications where continuous filtration and contamination control is necessary.