Do I really need DI Resin?

adova

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I am in a new house running off of a well system that also goes through a salt softener system. I bought a 7 stage RODI system without really thinking about it since my TDS had always been so high in previous homes (also, I like shiny new things).

Here, though, my input TDS is 6 and output is Zero before the Dual DI chambers. Besides TDS Reduction, is there anything else that warrants keeping the DI as part of the solution or should I save the hassle?

Secondary question - my water pressure is garbage. I have ordered a booster pump, but I really need to start filling a salt tub for some (real) live rock I am picking up this week. Any issues with just using the TDS 6ppm water directly for just the rock?
 

theMeat

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If your product water is zero you don’t need resin.
Your house water pump head pressure control box has adjustment to improve pressure without the need for a booster pump, unless there’s some other issue with your plumbing that is reducing pressure
 

JBNY

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0 TDS just means nothing conductive is left, DI is still needed to strip out things RO and TDS meters don’t see, like silica and boron. I have the same situation, zero TDS going to the DI, I still use DI.
 
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adova

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ok - I was not sure if the resin had other benefits outside of the TDS numbers.

The pressure is odd. I have a pressure tank set at 40 / 60 and the gauge reads that. It goes from that into a 1" pex then two 90 bends and then I tee off from the 1" to a 1/2". From that, it goes into another tee to a push connect 1/4" and directly into the RO system. I put the pressure gauge for the RO at the entry of the system and I cannot get better than 32 psi. Not sure what the issue is. I have even shut off water from beyond that point and it stays the same.
 
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adova

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0 TDS just means nothing conductive is left, DI is still needed to strip out things RO and TDS meters don’t see, like silica and boron. I have the same situation, zero TDS going to the DI, I still use DI.
Ok - that is what I was wondering / suspecting.
 

theMeat

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To clarify, I knew someone would bring up silica…
Silica and boron are present and needed in seawater. Too much isn’t good. Maybe run resin once to see how fast it gets used up. If it doesn’t last long you should probably continue using it
 

theMeat

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Or you could have your water tested to see if you need it
 

KStatefan

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It’s not typical but you can have low tds and still have hard water. And some ppl just like very soft water

How do you have Magnesium and Cacium Ions in the water to make it hard but low TDS? The water softener exchange the calcium and magnesium ions for sodium ions to make is soft but TDS stays about the same.
 

Randy Holmes-Farley

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I agree the water would not be hard at 6 tds.

It may be the case that some folks can use tap water directly, and others can use RO without a DI. I've considered the latter, but do not yet do it.

BUT, I would NEVER recommend taking either approach without a full test for problem ions such as copper by an ICP company.
 

Randy Holmes-Farley

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The 6 TDS is after the whole house water softener. Not sure what it is before that, but the iron and magnesium was very high/

Water softeners do not lower TDS. :)

Do you know what very high magnesium means in terms of a number?
 
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adova

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This was my water test before the water softener was installed:

1769695388316.png
 

Randy Holmes-Farley

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adova

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Thanks for the feedback. Sounds like I will keep the Resin as part of the solution. To circle back to the Live Rock - no major concerns using water directly after the whole house softener / filter just to keep it alive? Supposed to pick up 300 lbs tonight and I have no water made yet lol.
 

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