I have a Frankenstein pure water system that I’ve been building over the years. The current version is on a Wash-it Pro cart. It was a legacy white 10" Carbon filter housing. 40" stainless steel membrane housing with the standard Xero membrane. (Currently priced $340) and the older model 30" PVC Pipe with DI cartridge filled with virgin resin from Xero. The system sits horizontal in my truck at all times. The water in my area is very high TDS, around 400 on average.
My issue is I’m can’t seem to get my tds down to 0. On good days I hover around 20 and I get spots on hydrophobic windows unless I do a water only squeegee.
I know my RO membrane is starting to fail because its only bringing TDS down to 23% after less than a year. (That was probably my bad for not switching out my Carbon filter more regularly) But I’m debating on switching out my PVC DI tank for a 21" DI tank that is on the newer model Xero Pure sustems. (The one that feeds water from the cap) I notice that no matter how well I pack the resin currently, it always has a large gap after water runs through it. I assume I have channelling issues especially since it sits horizontal. I’m hoping the other 21" style DI tanks don’t have that issue. But even yesterday I changed out the resin on the job and I didnt get 0 TDS. It only brought the RO water from 44 to 18. So I’m a bit frustrated.
I also hope that I can keep the system horizontal since that works better in my small truck.