• Welcome back Guest!

    MARSH is a private reefing group. Comments and suggestions are encouraged, but please keep them positive and constructive. Negative threads, posts, or attacks will be removed from view and reviewed by the staff. Continually disruptive, argumentative, or flagrant rule breakers may be suspended or banned.

What’s up with my rodi (1 Viewer)

Users who are viewing this thread

RR-MAN

Guest
Joined
Aug 18, 2003
Messages
5,689
Reaction score
1,214
Location
Pearland
Please correct me if I’m wrong here, but that’s nonsense.. by the time water exits the RO membrane there should be no ammonia at all hitting the di resin. If that is truly the case there is a setup problem.

My guess is with the high output rates and high pressure pumps would be not enough contact time. Either way, ammonia / chloramine issues would be resolved with carbon. Some carbon works better than other, additional cartridges increase contact time and contamination removal.

You are wrong see above [emoji6][emoji4]

If your assumption was correct which I know it's not - we would've saved hundreds if not thousands by not changing so many chloramine/DI resin filters.
 
Last edited:

decimal

Supporting Member
Build Thread Contributor
Joined
Apr 20, 2007
Messages
2,521
Reaction score
1,134
Location
humble
just for clarification, "rejected by the RO Membrane" would mean RO Reject or Effluent that would not be a consideration since it is diverted as waste and not treated further. so not acted upon by the cation resin. Did you mean "pass through"?

When we speak about premature depletion of DI resin capability, we are speaking about ammonium ion as you mentioned above which is effectively removed by cation resin.

Prior to the RO membrane however, we deal with chloramine and the subsequent production of ammonia and chlorine and i stand corrected from my previous post in that carbon can address the chloramine but not the ammonia (Ammonium Ion). It is not clear to me if city water has high concentrations of Chloramine that is resulting in higher levels of ammonia, PH fluctuation or other factor(s) causing the DI resin to become prematurely depleted. Separate bed resins with a cheap primary bed should definitely be an effective way to address that but 1 cartridge for 200g seems excessive. Do you think a calcite cartridge to help stabilize PH could have a positive effect?
 
Last edited:

decimal

Supporting Member
Build Thread Contributor
Joined
Apr 20, 2007
Messages
2,521
Reaction score
1,134
Location
humble
You are wrong see above [emoji6][emoji4]

If your assumption was correct which I know it's not - we would've saved hundreds if not thousands by not changing so many chloramine/DI resin filters.

Sorry rr, could you elaborate a little on what you do know?
who is we? are you speaking for everyone who has ever had DI issues? ever or just a specific time range?

perhaps you could explain to a simpelton such as myself how ammonia affects the TDS measurements and contributes to the actual depletion of the DI Resin?
 
Last edited:
Joined
Jul 1, 2003
Messages
761
Reaction score
69
Location
Ohio
"Do you think a calcite cartridge to help stabilize PH could have a positive effect? "

I don't believe so.
 
Top