R/O Replacement Cartridges?

[Myka]

Try J&L Aquatics, or www.bulkreefsupply.com BRS has flat rate shipping and duty, so you don't get any hidden fees. They are awesome for RO stuff, and carbon, GFO, plumbing parts, etc.

You're going to want a 5 or 10 micron carbon block, and a 5 or 1 micron sediment prefilter. BRS has better carbon blocks and sediment filters than J&L, but the RO membrane is pretty universal. The jury is still out on the DI resin for me.