If your water has a normal amount of Total Dissolved Solids (i.e., 500 or less), you need at least 40 p.s.i. of
water pressure. Most homes on municipal water systems will have adequate pressure. If your shower water seems normal (when compared to hotels, your previous homes, your friends' homes, etc.), you probably have sufficient pressure. If you are doubtful about your pressure, you can buy a water pressure gauge at your local hardware store and measure the pressure. On the other hand, if your water has a high amount of Total Dissolved Solids (i.e., over 1500), you should probably have at least 60 p.s.i. of water pressure. If the TDS of your water is over 2000, then you should probably have at least 65 p.s.i. of water pressure. If you don't have enough pressure, you can buy a Booster Pump for your R.O. system, a Pressuriser for your whole house, a Permeate Pump, or possibly just run your R.O. system without a tank (the bladder in a tank creates back-pressure which has to be overcome). Please note that your pressure should not exceed 100 psi.
We sell an Aquatec ERP 1000 Permeate Pump for $60. It operates without electricity and reduces the back-pressure from your tank so that you can produce R.O. water at lower pressure. It has a two year warranty from the manufacturer. When you place your order, please specify whether you want Jaco fittings (screw thread connectors) or JohnGuest fittings (push in connectors).