Personaly save your money i got sucked into buying one paid $300 cdn it took a full 24hrs to fill a 33gall (reef tank) better off buying buckets and paying the LFS for their water its a lot more reliable too the carbon breaks down to quickly in a small home unit and to test it you need to spend $400. bannas on a electronic tester . Also whats your reason for an ro unit is it really needed? FNH.............
We charge $.85 a gallon for RO water. A decent RO unit will put out 30-50gpd. I suggest you have a few clean garbage cans ready for the RO water to be stored. Use the waste water for freshwater tanks.