Valuable MemberView Badges
- Aug 29, 2011
- Reaction score
- North Texas
Personally, I would just make changes to what you have. I would go with a 1 micron pre-filter. The zetazorb is most likely overkill. The prefilters will not lower tds, at least not with any significance. You have to realize the ro membrane is rated at .0001 microns. Then I would go with 2 carbon filters. You can do a BRS universal followed by their VOC or do a chloramine specific filter followed by a normal carbon filter. I would then ditch the dual membranes and go with just one. The dow filmtec 100gpd is now rated at 98% rejection so is a good choice or the 75 gal is also good and many seem to get 99% rejection rate with it. Also get a new flow restrictor. You can get the barrel type that you match the part to the gpd rated membrane you are buying. These just plug into the tubing but you can’t adjust them. There is also the capillary style that slides inside the tubing and you trim to change the flow but if you mess up you have to buy a new one. Third option is to buy a valve that allows you to make small changes to the flow. That way you can easily regulate the flow restriction. It all comes down to personal preference.Considering that I have chloramine treated water, I'd love to hear what you all suggest for either a new RODI unit (do I need multiple resin chambers?) or:
New membrane (maybe I'll go back to one)
Should I use catalytic carbon? Brand?
A regular carbon block (which one)? Or BRS Universal block?
A chloramine carbon block (which one - Matrikx chloraguard? 1 micron?)
And which DI resins if I use more than one?
I looked at the Spectrapure MaxCap, but it isn't chloramine specific, so I need to find one that is (or change out the filters)... Thanks,
You are currently seeing ammonia because the chloramine is being broken down by the carbon filter to chlorine and ammonia. The ro membrane does a horrible job at removing ammonia. That is the job of the di filter. In your case it appears the di filter is not working correctly between the ammonia reading and the tds reading. My guesses are it was not packed correctly, the di cartridge was installed upside down (been there, done that), or the media was bad.
The cation media is what will remove the ammonia. I would personally make all the changes above and just go with normal dual di media and see if that works but that is up to you. You can run a canister of cation before the dual di media to make sure it removes the ammonia.
Also ditch the auto shut off kit and add a flush kit that allows you to bypass the di media so you can get rid of tds creep. It is recommended you run the ro unit for a few minutes without running it thru the di media because the tds coming from the membrane will be really high for the first few minutes. It is basically a switch that allows you to switch the product water from the membrane between the waste water line and the di media line.