Great to see all the interest in RO - it is a cool technology/piece of equipment!
A few comments on the content of the guide:
In general, folks new to RO place too much emphasis on the "more is better" line of thinking. For a typical RO with an atmospheric tank treating chlorinated water, think of a 3 stage as your default configuration:
Sediment filter->carbon block->RO membrane
If you want a pressurized storage tank, you'll need to add a fourth stage - a "Taste and Odor Filter."
If your tap water contains chloramines, you'll want an additional. high end carbon prefilter.
It is the capacity of your RO membrane that drives the speed at which purified water will be produced. Realize that unless you provide factory spec conditions, you won't get the full production out of a membrane. The two most important factors in temps of speed of production are water pressure, and water temperature. The best residential-scale membranes in the US are made by (DOW) Filmtec. They are spec'ed at 77 degrees F and 50 psi. Other brands are typically spec'ed at 60 psi or 65 psi and 77F. Colder water and or lower water temperature will slow production. How much? We have a calculator for that here:
Reverse Osmosis Drinking Water System | RODI Systems | Home Water Filtration System - Buckeye Hydro
Regarding prefilters - The diagram shows the use of GAC as a prefilter - this is to be avoided. A carbon block will typically offer much better performance. If you see standard GAC used as a prefilter I'd question the expertise of the vendor - it is typically used because of it's low cost, not because of its optimum functionality. Carbon blocks are only very marginally more expensive.
Regarding the position of your "Probe 2" on the inline TDS meter, a better location for that probe would be BEFORE the Taste and Odor Filter as the RO water will pick up TDS going through that carbon filter.
Realize that the TDS of your RO water needs to be measured with the pressure tank valve CLOSED if your goal is to evaluate the condition of your RO membrane. Also be aware that the TDS of your RO water tells you nothing about the condition of your prefilters or when to change them. The answer to our first FAQ ("When should I change my filters?") addresses this issue in detail, here:
Reverse Osmosis Filters | RODI Systems | Commerical Water Filtration System - Buckeye Hydro
Russ