RODI question?

nikonosis · 03/11/2011, 08:38 PM

I just changed out all the filters in my RODI unit. The RO membrane is a filmtec dow. I am getting 135 TDS after the RO membrane and 55 after the DI.

Any idea why this is so high?

mikelaubach · 03/11/2011, 09:02 PM

Are the RO membranes one-way? I've never had to replace mine. If it is, and it is backwards, that could explain things.

nikonosis · 03/11/2011, 09:10 PM

They can only go one way.

Arthur1 · 03/11/2011, 09:17 PM

Hmmm.. the membrane is correctly seated, what is your incoming water pressure for starters? Also before running the the di with the new membrane did you flush the membrane out beforehand? Your last membrane I take it had lower readings on the TDS meter or was it not in place till now?

nikonosis · 03/11/2011, 09:25 PM

It had lower TDS and I ran the RO flush on the waste line. My auto shut off valve is also broken, I need to replace that. Could that be possibly causing a pressure problem? It makes a wooshing sound every 5-10 seconds or so. I do not know the water pressure, I don't have a gauge.

This is not the first time ive replaced the filters but it is the first time ive had TDS this high after a filter change.

Arthur1 · 03/11/2011, 09:55 PM

Doh, I should have asked some more questions..Is the membrane that you just put into use rated at the same gpd as the old membrane? If not did you replace the flow restrictor? If not it sounds like a culprit could be had. You know I have replaced Auto top offs that for w/e reason have failed but I honestly did not check to see if there was an interuption with the water pressure at the time other than that it was "enough" pressure that it should have worked correctly. If you still have a float in place I'd take off the shut off, do some line reconfiguration and give it a go and see if that "works" just remember to shut off the feed water bc as you know it'll keep flowing through the first two filters and membrane. But thats just me, always needing to know

nikonosis · 03/12/2011, 09:29 AM

I changed from a 125 down to a 75gpd. What do you mean flow restrictor? Do you mean the one on the waste water line?

nikonosis · 03/12/2011, 09:35 AM

Nevermind, I know what the flow restrictor is. Completely forgot to change that out...

Arthur1 · 03/12/2011, 12:07 PM

It happens! Should have asked you that one first though.

nikonosis · 03/12/2011, 02:56 PM

Now I am at 0 TDS after the DI, 10 after the RO membrane.

Buckeye Hydro · 03/14/2011, 05:02 AM

With that membrane, your RO water should be under 5 ppm (which would double the life span of your DI resin).

Russ

nikonosis · 03/14/2011, 06:25 AM

Its staying around 9 or 10 now, you know of anyway to get it down to 5?

The Velvet Sea · 03/14/2011, 08:27 AM

Maybe I missed it, but what is your tap water TDS?

Buckeye Hydro · 03/14/2011, 09:54 AM

New membrane, different capacity/higher rejection membrane, higher pressure.

You shouldn't be hearing any periodic whoshing sound... Would need more information.

do you want to call us when you are in front of the system?

Russ
513-312-2343

03/11/2011, 08:38 PM	#1
nikonosis Registered Member Join Date: Nov 2005 Posts: 1,935	RODI question? I just changed out all the filters in my RODI unit. The RO membrane is a filmtec dow. I am getting 135 TDS after the RO membrane and 55 after the DI. Any idea why this is so high? __________________ Home is where you hang your @ 75g rimless starfire 30x24x24, Bubble Magus NAC6, 2x Vortech MP10's and 1 MP40, MaxSpect G2-160 LED, Neptune Systems AquaController Apex/w wxm module, Eheim Compact+ 3000 Pump, Aqua UV Sterilizer, BRS GFO/Carbon reactor, Marine Magic doser, Aquahub DIY Top-it-Off Kit and Aqua Lifter Vacuum Pump

03/11/2011, 09:02 PM	#2
mikelaubach Registered Member Join Date: Sep 2007 Location: Durham, CT Posts: 1,367	Are the RO membranes one-way? I've never had to replace mine. If it is, and it is backwards, that could explain things. __________________ --MIKE-- Current Tank Info: 65G drilled, 10G sump, MCE600 skimmer, BRS dual carbon GFO rector

03/11/2011, 09:10 PM	#3
nikonosis Registered Member Join Date: Nov 2005 Posts: 1,935	They can only go one way. __________________ Home is where you hang your @ 75g rimless starfire 30x24x24, Bubble Magus NAC6, 2x Vortech MP10's and 1 MP40, MaxSpect G2-160 LED, Neptune Systems AquaController Apex/w wxm module, Eheim Compact+ 3000 Pump, Aqua UV Sterilizer, BRS GFO/Carbon reactor, Marine Magic doser, Aquahub DIY Top-it-Off Kit and Aqua Lifter Vacuum Pump

03/11/2011, 09:25 PM	#5
nikonosis Registered Member Join Date: Nov 2005 Posts: 1,935	It had lower TDS and I ran the RO flush on the waste line. My auto shut off valve is also broken, I need to replace that. Could that be possibly causing a pressure problem? It makes a wooshing sound every 5-10 seconds or so. I do not know the water pressure, I don't have a gauge. This is not the first time ive replaced the filters but it is the first time ive had TDS this high after a filter change. __________________ Home is where you hang your @ 75g rimless starfire 30x24x24, Bubble Magus NAC6, 2x Vortech MP10's and 1 MP40, MaxSpect G2-160 LED, Neptune Systems AquaController Apex/w wxm module, Eheim Compact+ 3000 Pump, Aqua UV Sterilizer, BRS GFO/Carbon reactor, Marine Magic doser, Aquahub DIY Top-it-Off Kit and Aqua Lifter Vacuum Pump

03/12/2011, 09:29 AM	#7
nikonosis Registered Member Join Date: Nov 2005 Posts: 1,935	I changed from a 125 down to a 75gpd. What do you mean flow restrictor? Do you mean the one on the waste water line? __________________ Home is where you hang your @ 75g rimless starfire 30x24x24, Bubble Magus NAC6, 2x Vortech MP10's and 1 MP40, MaxSpect G2-160 LED, Neptune Systems AquaController Apex/w wxm module, Eheim Compact+ 3000 Pump, Aqua UV Sterilizer, BRS GFO/Carbon reactor, Marine Magic doser, Aquahub DIY Top-it-Off Kit and Aqua Lifter Vacuum Pump

03/11/2011, 09:17 PM	#4
Arthur1 Registered Member Join Date: Oct 2007 Location: Cape Cod MA Posts: 578	Hmmm.. the membrane is correctly seated, what is your incoming water pressure for starters? Also before running the the di with the new membrane did you flush the membrane out beforehand? Your last membrane I take it had lower readings on the TDS meter or was it not in place till now?

03/11/2011, 09:55 PM	#6
Arthur1 Registered Member Join Date: Oct 2007 Location: Cape Cod MA Posts: 578	Doh, I should have asked some more questions..Is the membrane that you just put into use rated at the same gpd as the old membrane? If not did you replace the flow restrictor? If not it sounds like a culprit could be had. You know I have replaced Auto top offs that for w/e reason have failed but I honestly did not check to see if there was an interuption with the water pressure at the time other than that it was "enough" pressure that it should have worked correctly. If you still have a float in place I'd take off the shut off, do some line reconfiguration and give it a go and see if that "works" just remember to shut off the feed water bc as you know it'll keep flowing through the first two filters and membrane. But thats just me, always needing to know

03/12/2011, 09:35 AM	#8
nikonosis Registered Member Join Date: Nov 2005 Posts: 1,935	Nevermind, I know what the flow restrictor is. Completely forgot to change that out... __________________ Home is where you hang your @ 75g rimless starfire 30x24x24, Bubble Magus NAC6, 2x Vortech MP10's and 1 MP40, MaxSpect G2-160 LED, Neptune Systems AquaController Apex/w wxm module, Eheim Compact+ 3000 Pump, Aqua UV Sterilizer, BRS GFO/Carbon reactor, Marine Magic doser, Aquahub DIY Top-it-Off Kit and Aqua Lifter Vacuum Pump

03/12/2011, 12:07 PM	#9
Arthur1 Registered Member Join Date: Oct 2007 Location: Cape Cod MA Posts: 578	It happens! Should have asked you that one first though.

03/12/2011, 02:56 PM	#10
nikonosis Registered Member Join Date: Nov 2005 Posts: 1,935	Now I am at 0 TDS after the DI, 10 after the RO membrane. __________________ Home is where you hang your @ 75g rimless starfire 30x24x24, Bubble Magus NAC6, 2x Vortech MP10's and 1 MP40, MaxSpect G2-160 LED, Neptune Systems AquaController Apex/w wxm module, Eheim Compact+ 3000 Pump, Aqua UV Sterilizer, BRS GFO/Carbon reactor, Marine Magic doser, Aquahub DIY Top-it-Off Kit and Aqua Lifter Vacuum Pump

03/14/2011, 05:02 AM	#11
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	With that membrane, your RO water should be under 5 ppm (which would double the life span of your DI resin). Russ

03/14/2011, 06:25 AM	#12
nikonosis Registered Member Join Date: Nov 2005 Posts: 1,935	Its staying around 9 or 10 now, you know of anyway to get it down to 5? __________________ Home is where you hang your @ 75g rimless starfire 30x24x24, Bubble Magus NAC6, 2x Vortech MP10's and 1 MP40, MaxSpect G2-160 LED, Neptune Systems AquaController Apex/w wxm module, Eheim Compact+ 3000 Pump, Aqua UV Sterilizer, BRS GFO/Carbon reactor, Marine Magic doser, Aquahub DIY Top-it-Off Kit and Aqua Lifter Vacuum Pump

03/14/2011, 08:27 AM	#13
The Velvet Sea Registered Member Join Date: Oct 2006 Posts: 450	Maybe I missed it, but what is your tap water TDS? __________________ Current Tank: 75 gallon mixed reef

03/14/2011, 09:54 AM	#14
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	New membrane, different capacity/higher rejection membrane, higher pressure. You shouldn't be hearing any periodic whoshing sound... Would need more information. do you want to call us when you are in front of the system? Russ 513-312-2343

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