DI recommendation

[Darkfrog]

I have a 4 stage RO/DI currently set up with seidment-carbon block-75gpd TFC-mixed bed DI. I just bought a Spectrapure dual DI unit used and wnated to know the best setup for keeping silicates down.
I was confused by all of the DI choices on your website, DI-SB-10, DI-SB-CI-10, DI-AR-CI-10, DI-MB-CI-10, DI-MB-10....yada, yada, yada
It seems that some should go in front of others, but I can't figure out why. Now that I have the capacity for a 6 stage unit, I didn't know how I should set up. Should I run 2 carbon blocks prior to the RO membrane, instead of a third DI? What order of DI resins should I use. BTW I do have an inline purity meter as well as a handheld TDS. It looks like I have 1 stage more than the SpectraPlus 2000â„¢ :rollface: I should be able to make this a kick@ss water treatment setup.

[SpectraPure]

Yes, you could run 2 carbon blocks prior to the RO membrane, instead of a third DI.

The best two-DI cart setup for fish is the DI-SF-CI-10 followed by the DI-AR-CI-10. The SF will change color, and the purity monitor after the AR monitors its performance.

Scott
SpectraPure, Inc.

[Darkfrog]

Why do I need a color change cartridge if I have a purity monitor? Could I just continually test the water out of the first and when that is exhausted rotate the second to the first position and put a new one in the second position? If I do that should I use two DI-AR-CI-10s or should I still have a different cart in front of that one?

Do you suggest the smallest sediment and carbon like on the SP2000 or should I start with a 5 micron sediment, then 5 micron carbon, 0.5micron carbon?

[SpectraPure]

The SP-2000 uses one DI-SF-CI-10 followed by one DI-AR-CI-10.
They do different jobs, depend upon each other, and must be in that order. No rotation is allowed, except in our 4-stage Ultimate DI System where you can rotate 2 SF's and 2 AR's, independently of each other.

The many different kinds of DI carts are for many different scientific and industrial applications where all kinds of strange chemicals are being filtered out of the water.

We recommend the .5u sediment, then 1u carbon then .5u carbon.

Scott
SpectraPure, Inc.

[Darkfrog]

Got it, thanks.

[waves]

I have the SP2000 with the SF and AR DI cart. in sequence. Do both change color? The SF is just starting to change to a burgundy color at the bottom about one inch up from the charcoal/gray color of the cartridge after about 400 gallons. What is the life in thruput of these cartridges(ballpark as I know input quality will greatly affect)? Also ,when the SF is depleted based on color, should the AR be changed as well? How about the life expectancy on the carbon and sediment filters as well?

[SpectraPure]

From the manual:

Sediment Pre-Filter Diagnostic
For maximum contaminant removal and long membrane life, the sediment and carbon pre-filters must be changed when a 15% drop in pressure (40 p.s.i. minimum) is observed OR at least 6-month intervals. If your water contains a great deal of sediment or chlorine, the pre-filters may require more frequent changes to maintain adequate production rate and extended membrane life.


Carbon Block Filter Diagnostic
Replace the Carbon Block Filter when a 15-20% drop in pressure is observed OR at least every 6 months OR when chlorine breakthrough greater than 0.1 ppm occurs in the yellow concentrate line. To test for chlorine breakthrough , collect a 10 ml sample of the concentrate from the yellow tubing and test the chlorine concentration using test kit TK-CL-25. If the chlorine concentration is above 0.1ppm, replace the carbon pre-filter.

Deionization Cartridge #1 Diagnostic
( Second housing from the right )
The first DI stage is an anion cartridge #DI-SF-CI-10. In order to determine the condition of this cartridge, watch for the color to change from the bottom to the top. The color will change from a very dark blue to a lighter blue or tan color. Once the cartridge has changed color by 70 to 80% it must be replaced in accordance with the following instructions. (For “down flow” DI systems or systems that incorporate a permeate pump, the color will change from the top to the bottom ).There may be local conditions that affect the color-changing characteristics of this DI cartridge. High pH water (due to soda lime softening) may prevent this cartridge from changing colors.

Deionization Cartridge #2 Diagnostic
(Right-most housing)
The last stage is a dual layer cation/anion cartridge, or in some cases a mixed bed DI. The condition of this cartridge should be judged by observing either a RED or GREEN light indication from the monitor. Please note that the probe is located after Stage #4. Thus, the monitor indicates the condition of the fourth stage cartridge.
Turn the on the system and allow water to flow past the monitor probe for at least 20 minutes before attempting to use the monitor. The monitor will indicate GREEN when the cartridge is in good condition and RED if it is exhausted and in need of replacement. (Be sure that switch #7 is in the ON position and all other switches are OFF.)

Note: In addition to the monitor indicating the DI cartridge condition, the resin will also change color. Note that only the DI-AR-CI-10 cartridge is color indicating, not the lab grade mixed bed cartridge.
The DI-AR-CI-10 cartridge’s violet-colored layer is the resin layer used to indicate exhaustion and will change to an orange color when exhausted. The standard cartridge will change color from bottom to top while the “down-flow” version will change from top to bottom.
The color change that occurs in this stage gives a general indication of its condition but the monitor will provide the most accurate diagnosis of its condition. There may be local conditions that affect the color-changing characteristics of these DI cartridges. High pH water may prevent these cartridges from changing colors.
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We try to promise at least 400 gallons per cartridge pair, you will get more depending upon how good the membrane is at removing the majority of contaminants.

Hope this helps,

Scott
SpectraPure, Inc.

[waves]

Thanks.