The 5-stage H6500 is the most efficient RO system on the market.  It features a proprietary permeate pump that increases water efficiency by over 300%, wasting far less water to drain.  This can be beneficial for connecting to septic systems.  The H6500 also allows water production at lower pressures, increases the dispensing pressure to within five (5) pounds of line pressure, and makes water three (3) times faster than our competitors. 

The H6000 is also a 5-stage RO system having the same quality and details as the H6500.  It simply lacks the high efficiency permeate pump, which reduces water efficiency to match industry standards.