My tap is at 65 psi and it's a 150 gpd membrane. I had a booster pump but it only improved production from 1:1.7 to 1:1.6 so I didn't use it. For me the biggest difference in production is incoming temperature. Cold tap water this time of year is 4-6C and in summer it is 8-12C. If I boost it up to 20C then my production almost doubles.
I'm not concerned too much about DI as it hasn't been a problem -even dealing with ammonia in the RO water from chloramines I just replace the DI when I replace the prefilters...it's pretty burned up by then.
My tap water is 180-220 and has chloramines so I run two carbon filters. My membrane is 4 years old or something and is running at 8 ppm last time I checked. I flush it lots. It's holding it's own.
