As I said in the earlier post, you really need about 50psi. If you're below 40psi, you need a booster pump to get decent performance from the unit. Having two pressure gauges (see pics) will tell you when you need to change filters. A TDS
meter ($40 or so) will alert you when to change RO
membranes or DI
cartridges. A hydraulic shut off coupled with a float valve in the reservoir will solve the turning it on and off. A Rubbermaid Brute trash can makes an excellent container. If you're worried about an overflow, put an emergency drain right at the top of the container and run it either outside or tee it into a drain line under the house. I can send you some pics of how all this is set up if you are interested in doing any of this. You also should rig a backflush valve on your unit so you can backflush the membrane once in a while...it'll last longer and work better.