Reverse osmosis systems work very well at removing all types of minerals and contaminants in the water. Hard water minerals are easily removed from the reverse osmosis membrane as well but it does this job all too well.  Hard water minerals go through the veins of the membrane and slowly build scale all along the veins which can cause the membrane to eventually clog.  Dow Filmtec recommends that their membranes work under water conditions that have less than 3 grains of hardness but a large majority of homes do not have this ideal situation.  In real world applications under residential use, if you have extremely hard water where it’s over 15-20 grains of hardness. Under commercial or industrial applications, you may want to consider the 3 grains recommendation.

Residential reverse osmosis systems do not really produce large amounts of water over time and the replacement reverse osmosis membranes do not cost that much when compared to an industrial ro system.  Industrial reverse osmosis systems produce water constantly and have a tendency to clog more quickly because of it. Adding a water softener to larger commercial systems is not only recommended but required to maintain warranty with your reverse osmosis system.  If not, your system will mostly clog and you will have no water production as well as a large bill to replace those expensive membranes.

Water softeners not only help the reverse osmosis system with the scale build up but it will also increase the longevity of the membranes.  Reverse osmosis membranes work better with sodium and potassium ions versus the calcium and magnesium.  They find these ions better and easier to reject.  Softening your water doesn’t have to involve a full system costing thousands of dollars – although it is recommended to have a system that regenerates itself.  It can be as easy as changing out one of your filter cartridges for a water softening cartridge.  It may cost more in the long run using softener cartridges but you don’t have to hassle yourself with getting a new water softener system installed for the whole home or office.

So under the right conditions, you may want to consider getting a water softener with a reverse osmosis system to make sure your get the best life out of your reverse osmosis system. In the long run, you will be saving money, time, and saving yourself from a headache.