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swk
04/10/2015, 05:56 PM
I have a unit that gets roughly 75 lbs pressure feed to the first membrane. If I piggy backed 2 99% RO membranes would I get the increased efficiency or should I just look at upgrading to a better single RO unit?

thanks!

SpectraPure
04/11/2015, 02:22 PM
75 psi is good, no matter what system you have.

If you refer to "efficiency" as saving water then you are looking for a lower waste:product ratio. The ability to have lower ratios is directly related to how hard the tap water is (and not the %-rejection value).

The harder the water, the more waste water is needed to keep the membrane free from scaling. If the tap water hardness is less than 180 ppm, then you can have a 2:1 ratio.

So, for a given hardness and current proper ratio, if you double the membranes, you have to have a flow restrictor that doubles the waste water.

Support at SpectraPure

swk
04/11/2015, 08:13 PM
So, my tap measures at 168ppm, so you're suggesting I could get a 2:1 ratio, everything after that lost me a bit lol!!!

SpectraPure
04/11/2015, 08:25 PM
Yes. Try adding more restriction to the waste water line, usually with a ball-valve.

swk
04/11/2015, 08:29 PM
Ok. This could be accomplished with using your 99% membranes, correct?

SpectraPure
04/13/2015, 09:34 AM
The 99% membranes are qualified with a 5:1 ratio. At 2:1 your mileage may vary a bit, but it will be better than the membrane you are using now.

swk
04/13/2015, 09:37 AM
Tested my rodi as I was curious yesterday.

168ppm from tap
3ppm after ro before di

In 60 sec

335 good
840 waste

2.5 : 1

Seems like things are already pretty efficient?

SpectraPure
04/13/2015, 09:51 AM
Yep.

SpectraPure
04/13/2015, 09:58 AM
What are your TDS readings?

Jeremy

swk
04/13/2015, 10:02 AM
168 from tap
3 after ro
0 after di

SpectraPure
04/13/2015, 10:16 AM
Smooth Sailing!

Jeremy

swk
04/13/2015, 10:18 AM
Thanks guys. Love your stuff. I'm a lm3 doser and love your filters.

Would a maxcap 2:1 increase my ratio at all?

SpectraPure
04/13/2015, 10:24 AM
Only from 2.5:1 to 2:1. You have a 98.6% membrane at this ratio. Decrease the ratio and you may see the %-rejection go down a bit.

swk
04/13/2015, 10:25 AM
Gotcha. Thanks for all the help

SpectraPure
04/13/2015, 10:25 AM
Ok.

SpectraPure
05/12/2015, 10:58 AM
I just noticed something. Do you know what your water hardness is on the tap?

Jeremy

swk
05/12/2015, 11:04 AM
As far as tds?

SpectraPure
05/12/2015, 11:07 AM
No, General hardness GH

swk
05/12/2015, 11:08 AM
You know, I'm not sure. I can see if I can find it in my local water report, or grab an api kit?

What's your thinking here, Jeremy?

SpectraPure
05/12/2015, 11:20 AM
Well,

If you have more than 180ppm of general hardness I would not recommend reducing the waste past 3:1

JEremy

swk
05/12/2015, 11:32 AM
Good to know. Let me check and I will post what I can find here

swk
05/12/2015, 11:45 AM
Jeremy - according to water report total hardness, as CaCO3 is 140ppm. Is this the correct type of hardness?

SpectraPure
05/12/2015, 11:48 AM
Sounds good

Jeremy

swk
05/12/2015, 12:01 PM
Thanks for keeping up on this man. I really appreciate it.

SpectraPure
05/12/2015, 01:27 PM
Hey no problem man. It's what I do.

Jeremy

Breadman03
05/12/2015, 01:49 PM
Hey no problem man. It's what I do.

Jeremy

'Tis how you got my business.

SpectraPure
05/12/2015, 05:38 PM
That's the way it should be. There is a certain value that people overlook in a long forgotten practice called customer service. It has been blinded by the low price tag syndrome.

=)

Thanks for being a loyal customer!!!

Jeremy

SpectraPure
05/15/2015, 12:32 PM
Any word

Jeremy

swk
05/15/2015, 12:45 PM
Jeremy - according to water report total hardness, as CaCO3 is 140ppm. Is this the correct type of hardness?



Any word



Jeremy


Did that post answer your question?

Also - is it you that I've been emailing with regarding my lm3?

SpectraPure
05/18/2015, 11:42 AM
Yes it did. You can run 2:1 no probs. Whats wrong with your lm3?

Jeremy

swk
05/18/2015, 11:43 AM
Yes it did. You can run 2:1 no probs. Whats wrong with your lm3?



Jeremy


It's been randomly switching to "all pumps off" screen.

SpectraPure
05/19/2015, 11:33 AM
The pump needs servicing, and the hours need to be reset to 0. Follow the maintenance section of the manual. If the hours are not reset the pump wont go.

JEremy

swk
05/19/2015, 11:37 AM
Thanks! Check your pm when you have a monent

SpectraPure
05/19/2015, 02:33 PM
Will do! Thanks! =)