RO Issues

[KJAG]

I have a Spectrapure Maxcap 180 manual flush with an added fifth stage and a DI bypass installed, and am all of a sudden having issues after about a year and a half with this particular unit.
Currently my params are as follows as listed by multiple TDS meters

In from Tap TDS: 710
Out from membrane: 006
In DI:000
Out DI:000

My value for the membrane output jumped drastically about a week ago and wasnt resolved by swapping all of the filters except for the membranes.
Re-tested after new filter swap and my membrane output was still approx 75 TDS
At this point, decided to just swap everything and sprung for two new membranes. All filters/membranes are Spectrapure and are all brand new.

Have it plumbed as follows: Sediment, Carbon, Chloramine(my municipal water supply adds Chloramines), DI MC, DI SB..
Ive triple checked that the membranes (and filters) are seated properly and all seals are tight.

Ive troubleshot everything I can personally think of and cant figure out why my membrane TDS isnt reading 000.

Any thoughts from those who know RODI appreciated.

 

[twilliard]

@AZDesertRat can help!

 

[KJAG]

Thanks yeah pm'd him a few mins ago.

Oh: pressure to the unit is about 60

 

[AZDesertRat]

If I understand correctly you are saying your RO only TDS jumped from 6 to 75? You replaced the sediment and carbon and it did not change? This isn't surprising since TDS is 0.0001 microns and smaller and filters are 0.5 microns, thousands of times larger and designed to remove big stuff. Then you replaced the membranes and it still did not go down?

A couple of thoughts and observations. First 60 psi is a little too low for a dual membrane system, 65 psi is the recommended minimum pressure. Second is I would forget the chloramine carbon, it is a waste of money and further reduces the pressure available to the membranes. If it were needed Spectrapure would have included it standard. They use the absolute best 0.5 micron carbon blocks which are more than capable of removing the chlorine portion of chloramines and breaking the bond with the ammonia which is mostly removed by the membrane and polished off by the dual DI.

Did you flush each new filter sequentially when you installed them and disinfect the system per Spectrapures recommendations while you had it down? Did you make a minimum of 3-5 gallons, probably twice that with dual membranes to flush out the new membranes before installing the DI filters?

What are you testing the TDS with and how? What is your exact measured waste ratio currently? What is your tap TDS, RO only TDS from each membrane individually and for each individual DI stage? What is your water temperature and lastly are you using softened water?

 

[Elysium]

I think they meant that the output from the new membranes is reading 6 TDS (old membrane was the one that jumped to 75).

6 TDS out from the new RO membranes with an initial tap TDS of 710 is still a 99% rejection rate. That's pretty standard for most RO membranes.

 

[AZDesertRat]

99% is much better than most membranes which test out at 96-97% off the shelf. This is why Spectrapure stands out from the crowd with their specially treated membranes and their individually hand testing and guaranteeing their Select series 99% membranes.

 

[KJAG]

If I understand correctly you are saying your RO only TDS jumped from 6 to 75? You replaced the sediment and carbon and it did not change? This isn't surprising since TDS is 0.0001 microns and smaller and filters are 0.5 microns, thousands of times larger and designed to remove big stuff. Then you replaced the membranes and it still did not go down?

A couple of thoughts and observations. First 60 psi is a little too low for a dual membrane system, 65 psi is the recommended minimum pressure. Second is I would forget the chloramine carbon, it is a waste of money and further reduces the pressure available to the membranes. If it were needed Spectrapure would have included it standard. They use the absolute best 0.5 micron carbon blocks which are more than capable of removing the chlorine portion of chloramines and breaking the bond with the ammonia which is mostly removed by the membrane and polished off by the dual DI.

Did you flush each new filter sequentially when you installed them and disinfect the system per Spectrapures recommendations while you had it down? Did you make a minimum of 3-5 gallons, probably twice that with dual membranes to flush out the new membranes before installing the DI filters?

What are you testing the TDS with and how? What is your exact measured waste ratio currently? What is your tap TDS, RO only TDS from each membrane individually and for each individual DI stage? What is your water temperature and lastly are you using softened water?

Prior to buying any new filters, my tds from the membrane was alarmingly high. Like 250'ish. I didnt realize until my wife complained our drinking water tasted "different." I then bought new sediment, carbon, chloramine and DI resins and replaced all 5 stages. Re-tested TDS on the RO and it was still reading at 75.
At that point I pulled the trigger on two new membranes since I figured that would have to be the culprit, which makes my system brand new aside from the skeleton of plastic that its made of. Figured this would be the answer.
I flushed the membranes per Spectrapure's rec's and made approx ten gallons of RO to see if the membrane TDS would drop. As I type this Im still getting readings of 008 TDS. I used to get readings of 000. Thats with every single filter/membrane being replaced, fully seated, etc.

As far as the chloramine block being a waste of $: well, any further thoughts on that would be appreciated. I was burning through DI ridiculously fast at one point and I troubleshot with Jeremy @spectrapure, and we analyzed my municipal water charts and deduced that my tap is loaded with chloramines and a high CO2. He was the one who recommended I add the fifth stage, and it did prolong my DI life.
As far as the current pressure of 60 being low: I dont mind getting a booster. Money isnt an issue. I just cant comprehend why I was functioning smoothly for so long and now I cant keep a membrane TDS of less than 008 when I had previously been running 000. Perhaps the CA drought is responsible and my water now has substantially more TDS? But even still: a TDS of roughly 700 out of the tap doesnt seem outrageously high compared to other parts of the country..

Per your questions, my Tap TDS is 710, RO only is 008, DI is reading 000 in and out, Temperature: Not sure. Waste ratio of 2:1. And I do not use a water softener due to my other hobby of gardening. Salts are not an option in my water supply for my gardens.
Thanks appreciate the feedback.

 

[AZDesertRat]

You mention you are using this for drinking water too? How is it plumbed? This can be a big game changer. If you do not have the DI isolated from the drinking water you have an issue. It should be plumbed with a check valve like this:
http://spectrapure.com/huds/4-STAGE-DWK-RODI-NAG.pdf so TDS creep does not eat your DI.

With a tap TDS of 710 and hard water your waste ratio should be no less than 4:1, there is no getting around this. I had the same system here in Phoenix and the 4:1 waste ratio is the most critical piece of the puzzle, without that membranes are doomed. If you were using softened water you could possible reduce that to 3.5:1 but no less as the TDS going in would exceed the 710 you have now but would be a little easier for the membrane to process since most of the calcium would have been removed by the softener and membranes are better at removing sodium. If you had a softened water TDS of around 250 or less you could get away with 3:1. there is no way on earth you can have 2:1 and get decent membrane life above around 150 softened TDS. Membranes must be continuously flushed via the waste line, there is no getting around that fact period.

You will never ever get 0 TDS out of a RO membrane, it is physically impossible. A RO membrane is a 90-99% efficient device. I take it you are relying on inline TDS meters which are about as accurate as litmus paper. I let the batteries die in both of my dual inlines years ago. Invest in a good ATC handheld meter which is much more accurate, much more versatile and can be calibrated. Inlines lack ATC so if your water and air temperatures vary by much they are inaccurate, and water and air are rarely the same.

If you do not want to use a water softener, which I use myself but plumbed the exterior hose bibs so they provide unsoftened water except one which is used for car washing, then you need to increase your waste ratio to no less than 4:1 ASAP or you will soon be buying membranes again.

Co2 is a killer of DI resin. It is a gas so passes through membranes. The only thing you can do is send the ROI only water through a degassing tower where you bubble air through a column of RO water to drive the Co2 out then pass the degassed water through the DI later. I will say again the chloramine filter is a waste of your money, Spectrapure's 0.5 micron carbon block is more than capable of removing the chlorine portion of chloramines and breaking down the bond with the ammonia which is removed by the RO membranes and the DI resin. Chloramine carbons DO NOT remove chloramines, they do exactly what the 0.5 micron carbon block does. The EPA limits chloramines in drinking water to the same 4 mg/L or PPM that free chlorine is limited to so its no big deal.

The average TDS nationwide is 250 so 700 is very high. I vary between 560 and 850+ here in Phoenix but some parts of the country are around 50. More important than TDS though is hardness, calcium and magnesium are very hard on membranes. All RO membrane manufacturers recommend softened water and none will honor a warranty claim if softened water was not used. The absolute best thing you can do for an RO membrane hands down.

 

[KJAG]

You mention you are using this for drinking water too? How is it plumbed? This can be a big game changer. If you do not have the DI isolated from the drinking water you have an issue. It should be plumbed with a check valve like this:
http://spectrapure.com/huds/4-STAGE-DWK-RODI-NAG.pdf so TDS creep does not eat your DI.

With a tap TDS of 710 and hard water your waste ratio should be no less than 4:1, there is no getting around this. I had the same system here in Phoenix and the 4:1 waste ratio is the most critical piece of the puzzle, without that membranes are doomed. If you were using softened water you could possible reduce that to 3.5:1 but no less as the TDS going in would exceed the 710 you have now but would be a little easier for the membrane to process since most of the calcium would have been removed by the softener and membranes are better at removing sodium. If you had a softened water TDS of around 250 or less you could get away with 3:1. there is no way on earth you can have 2:1 and get decent membrane life above around 150 softened TDS. Membranes must be continuously flushed via the waste line, there is no getting around that fact period.

You will never ever get 0 TDS out of a RO membrane, it is physically impossible. A RO membrane is a 90-99% efficient device. I take it you are relying on inline TDS meters which are about as accurate as litmus paper. I let the batteries die in both of my dual inlines years ago. Invest in a good ATC handheld meter which is much more accurate, much more versatile and can be calibrated. Inlines lack ATC so if your water and air temperatures vary by much they are inaccurate, and water and air are rarely the same.

If you do not want to use a water softener, which I use myself but plumbed the exterior hose bibs so they provide unsoftened water except one which is used for car washing, then you need to increase your waste ratio to no less than 4:1 ASAP or you will soon be buying membranes again.

Co2 is a killer of DI resin. It is a gas so passes through membranes. The only thing you can do is send the ROI only water through a degassing tower where you bubble air through a column of RO water to drive the Co2 out then pass the degassed water through the DI later. I will say again the chloramine filter is a waste of your money, Spectrapure's 0.5 micron carbon block is more than capable of removing the chlorine portion of chloramines and breaking down the bond with the ammonia which is removed by the RO membranes and the DI resin. Chloramine carbons DO NOT remove chloramines, they do exactly what the 0.5 micron carbon block does. The EPA limits chloramines in drinking water to the same 4 mg/L or PPM that free chlorine is limited to so its no big deal.

The average TDS nationwide is 250 so 700 is very high. I vary between 560 and 850+ here in Phoenix but some parts of the country are around 50. More important than TDS though is hardness, calcium and magnesium are very hard on membranes. All RO membrane manufacturers recommend softened water and none will honor a warranty claim if softened water was not used. The absolute best thing you can do for an RO membrane hands down.

As mentioned, I have the DI totally isolated from the RO via ball valves(DI Bypass) . Assuming this accomplishes the same goal as the check valve.

Interesting thoughts on the isolated water softener and sounds like thats what needs to happen. I absolutely despise soft water in the home and its the worst thing you could possibly water your garden or lawn with, but isolating it to one outlet strictly for the RODI unit is doable. Ill get on board if it will prolong RODI components.

Regarding the inline TDS meters and my variables of 008: So you are saying my readings are acceptable and appropriate as of now, with new membranes, and new filters? If so, I am left wondering why I was getting readings of 000 before..

Finally, how does one go about increasing their ratio to 4:1?

Thanks for the thoughts.

 

[AZDesertRat]

The differences between 000 and 008 show the inaccuracy of the inline meters. You will never have a true 0 TDS with RO only, it's not possible. The water temperature was probably colder and further from the room temperature at the time you saw the 000. The probes on the inlines actually measure air temperature not the water as with an ATC handheld. I like accuracy and a sensitive meter so use the HM COM-100 which is ATC compensated and actually does read in decimals down to tenths of a ppm.

To change the waste ratio you buy a new $6 untrimmed capillary tube flow restrictor and trim it to fit your exact and unique water conditions.

Your rejection rate or removal efficiency is 98.87% or right at the 99% which is very good for a dual membrane system which sends the concentrated brine or waste from the first membrane to the second so it has to work even harder and with your marginal pressure which should be higher for dual membranes.

 

[KJAG]

The differences between 000 and 008 show the inaccuracy of the inline meters. You will never have a true 0 TDS with RO only, it's not possible. The water temperature was probably colder and further from the room temperature at the time you saw the 000. The probes on the inlines actually measure air temperature not the water as with an ATC handheld. I like accuracy and a sensitive meter so use the HM COM-100 which is ATC compensated and actually does read in decimals down to tenths of a ppm.

To change the waste ratio you buy a new $6 untrimmed capillary tube flow restrictor and trim it to fit your exact and unique water conditions.

Your rejection rate or removal efficiency is 98.87% or right at the 99% which is very good for a dual membrane system which sends the concentrated brine or waste from the first membrane to the second so it has to work even harder and with your marginal pressure which should be higher for dual membranes.

Copy thanks.
I'm guessing this is the flow restrictor I need?
http://spectrapure.com/FILTERS-MEMB...-RESTRICTORS/Flow-Restrictor-Standard-180-GPD

In regards to a water softener, do they make a model where I can simply attach to a cold water sink outlet instead of plumbing it to the water main? Or would doing so further reduce pressure from that connection. If that makes sense..

I double checked the pressure gauge and it actually reads right at 65 which is the minimum apparently. What's ideal in terms of pressure to a dual membrane system?

 

[AZDesertRat]

Yes that is the restrictor. You would trim it following the directions in your owners manual, usually starting on about page 8.

The higher the pressure the more efficient membranes are. I run am Aquatec 8800 booster at 95-100 psi and my RO is at 99.43% rejection rate on softened water going in between 560 and 850 TDS and coming out between 2 and 3 TDS RO only. The MaxCap DI lasts over 1000 gallons and SilicaBuster over 3000.

They make smaller RV type softeners that work pretty well. It will reduce the pressure a little but might be worth it.

 

[KJAG]

Copy thanks a million.

Last question: For now...

Can you explain why running a water softener inline doesn't in itself exhaust the membranes? How is your TDS not exponentially spiked after passing through salts prior to running through the membranes?

 

[KJAG]

@AZDesertRat

AZ, about to pull the trigger on this unit per discussion earlier in this thread. Wanted to run it by you first if you don’t mind weighing in w your thoughts (at your convenience)
Thanks in advance

Shores

https://www.amazon.com/Watts-RV-PRO-1000-M7002-Water/dp/B0050EITTK

 

[Opus]

Hope you get a reply. He hasn't been on since May. I asked if anyone knew what happened to him but got no replies.

 

[KJAG]

Hope you get a reply. He hasn't been on since May. I asked if anyone knew what happened to him but got no replies.

Bummer hope he’s alright..

 

[cromag27]

i don't know about this specific unit, but any softener PRE rodi is going to help out.

azdesertrat comes and goes periodically. right now he's gone.

@AZDesertRat

AZ, about to pull the trigger on this unit per discussion earlier in this thread. Wanted to run it by you first if you don’t mind weighing in w your thoughts (at your convenience)
Thanks in advance

Shores

https://www.amazon.com/Watts-RV-PRO-1000-M7002-Water/dp/B0050EITTK

 

[KJAG]

i don't know about this specific unit, but any softener PRE rodi is going to help out.

azdesertrat comes and goes periodically. right now he's gone.

Well he does, and he covered that already, but thanks.

 

[Whipples]

In AZ’s absence I would give spectrapure themselves a ring. They’ve been helpful with me in the past and this is all they do!

As for water softeners, I’m not sure how much experience the reefing community has, so maybe try for some home improvement forums to see what people had success with? A softener that brings tds down will improve the membrane life and efficacy, but keep an eye on the DI media.

 

[KJAG]

In AZ’s absence I would give spectrapure themselves a ring. They’ve been helpful with me in the past and this is all they do!

As for water softeners, I’m not sure how much experience the reefing community has, so maybe try for some home improvement forums to see what people had success with? A softener that brings tds down will improve the membrane life and efficacy, but keep an eye on the DI media.

Their customer service is terrible but I’m still sold on their products. For now.. I added a softener and the flow restrictor AZ recommended and I’m good to go. RO is at approx 7ppm now. (DI is zero)