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J3REEF
12/17/2011, 08:56 AM
Filterguys,

Just added a few things to my RO/DI system, thanks for the equipment, and have a question.

The new setup is a ocean reef+1 which outputs to a newly added single stage filled with a anion silica cartage which outputs to a newly added tsunami two stage DI system.

Prior to this the setup was the ocean reef +1 5 stage. Just slid the DI down via the added tsunami and put in the single anion stage.

Two dual TDS meters and the question is TDS levels after the anion stage.

TDS into the system is ~390, out of the 4 stage is ~3 which flows into the anion stage, out of the anion stage is ~20???, out of the dual DI stage is 0.

So, the question is why would I have a bump in TDS from ~3 to ~20 after hitting the anion cartage???

PSI is ~60

Thanks!
J3reef

Thefilterguys
12/19/2011, 02:37 AM
What you are seeing is a normal reaction when cation an anion resins are run seperate, it is an ion charge created by bonding and compound change and it is the reason an anion stage must be run before a mixed bed resin or a cation resin. the two resins or an anion and a mixed bed resin balance the charge and complete the de-ionization.

Jim

J3REEF
01/05/2012, 12:05 PM
Thanks again for the gear and support.
System running great with the upgrade.
I now have:

PSI 60
tap water in-> TDS in 354
Stage One POLY SEDIMENT FILTER 5 MICRON
Stage Two MATRIKX CTO CARBON BLOCK FILTER
Stage Three CTO PLUS (MATRIKX +1) CARBON BLOCK FILTER
Stage Four RO membrane 75 GPD Dow FilmTec - TDS out 4
Stage Five ANION SILICA CARTRIDGE - TDS out 8
Stage Six COLOR CHANGING DI RESIN
Stage Seven COLOR CHANGING DI RESIN - TDS out 0

First question - when do you recommend to change the ANION silica?
Second question - how do the numbers look at each stage?

Thefilterguys
01/05/2012, 03:49 PM
You are getting almost 99% rejection rate which is great. I would run the DI's until you see an inch or two of color change in the second DI (stage seven) then change anion and first DI and rotate the last cartridge into (stage six) position.

Jim