The Rainsoft UF50 reverse osmosis drinking water system is a three stage system. We sell filters for all three stages. The Rainsoft UF50 RO system and all three stages can be found here:
http://www.waterfilters.net/Rainsoft...e_p_0-908.html
The first stage of the Rainsoft UF50 can be replaced by the compatible Pentek EPM-10 water filter:
http://www.waterfilters.net/Pentek/w...ers/EPM-10.htm
The replacement reverse osmosis membrane for the Rainsoft UF50 is the Rainsoft TFC-RS9-50 membrane:
http://www.waterfilters.net/Rainsoft...e_p_0-908.html
The third stage of the Rainsoft UF50 can be replaced by the compatible Pentek CBC-10:
http://www.waterfilters.net/Pentek/w...ers/CBC-10.htm
The optional fouth stage of the Rainsoft UF50 is the Omnipure CL6ROT33-B granular activated carbon filter. The Omnipure CL6ROT33-B can be installed after the reverse osmosis water storage tank. The CL6ROT33-B by Omnipure will remove any particles, tastes and odors your water has from sitting in the water storage tank. The Omnipure CL6ROT33-B can be found here:
http://www.waterfilters.net/Omnipure...r_p_0-754.html