RO/DI Membrane question

[Myka]

You can do whatever you want to do. I think Calgary water is around 200-300 ppm out of the tap? DI resin will only remove up to 20 ppm, and it will burn out very quickly if it is indeed being fed water of 20+ ppm. Now, if you lived in the lower mainland where the tap water is often less than 20 ppm then running just DI is definitely a reasonable option. I wouldn't do it though. DI won't remove all the things that RO will, same that RO won't remove all the things DI will.