I've attempted to reach out to BRS customer service, but it got me nowhere. Here is the situation: I initially purchased the 4 stage value plus RODI unit from BRS. I began having issues with diatoms and decided to upgrade to the 5 stage. After a couple of months of getting nowhere with the diatoms i upgraded one again, to the 7 stage. Here is where my concern lies. When I turn the unit on, after the sediment filter, the first carbon stage fills with water, I then notice my pressure gauge rise to 60 psi. This is BEFORE the second carbon stage fills with water. Maybe I'm wrong but shouldn't both carbon stages fill first, THEN the RO membrane? I believe I screwed something up between the first and second upgrades while modifying my unit to make drinking water as well. I have attached my attempt at a schematic. If pictures are needed I will be more than happy to upload them. Whatever I need to do so one of you can help me! Like I said, I sent all this info to BRS and all I got was a link for installing an auto shutoff valve. They said they didn't have schematics for a 7 stage unit...seems like this should be a simple fix if I could find the right info! Thanks in advance.