RO System help

[brew703]

Been brewing for a couple years now and alternate between distilled and filtered water (from one of those stand alone machines). From a cost perspective, $7 per brew for distilled vs $1.50 for the filtered water I've been buying.

The local Wal-Mart has a Primo water machine (self serv) but every time I go to fill my jug it's down. There is a filtered water machine by my house that I used to get water from ($1 for 5 gal) but it's not RO and the water is inconsistent plus the machine it's pretty dirty. Just really tired of going to fill my jug only to find out the machine is down then I have no choice but to go with distilled.

I've been throwing around the idea of getting a RO system but every time I get ready to pull the trigger I talk myself out of it.

Seems there are pro's and cons to all systems I have looked at and I think that's part of the reason why I talk myself out of it. Plus the cost factor. it would take me approx. 21 brews to break even which would be over a year.

I was going to just get one of the inexpensive units from Ebay but don't want the inline filters most of these use. So I found a couple that I am contemplating so would like some opinions.

#1 is a 5 stage unit from Ebay for $95. Overkill I know but there are not many 3 stage filters on the market. What I don't like about this unit is the stage 2 and 3 are the same filter so if I were to get this unit I would replace stage 3 with a 1 Micron carbon block filter. Also the RO membrane isn't a Filmtec. This would increase my cost approx. $15. Also this unit doesn't have a flush valve but I could add that for another $5-10. So now I'm at $115 to $120.
here's the link: http://www.ebay.com/itm/50-GPD-Drin...d=271575999878&_trksid=p2045573.c100033.m2042

#2 is a system from Bulk Reef Supply. it's a 4 stage which is what I want but the stage 1 and 2 are both 5 micron filters. I would prefer they would at least be 1 micron or 1 micron and .5 micron.
I'm kinda leaning towards the unit from BRS.
here's the link: https://www.bulkreefsupply.com/brs-4-stage-ro-only-system-75gpd-2.html

Any help in deciding would be appreciated.

 

[mabrungard]

I suggest that you contact Buckeye Hydro to obtain the custom system that you want. It may be more competitive than you expect since you can include just the components that you really need for your uses.

 

[day_trippr]

I'd start by obtaining a solid water report...

Cheers!

 

[ScrewyBrewer]

While you may not like the price, I bought the SpectraPure CSP RO 90-AF reverse osmosis water filtration system. It has a lot of useful features and functionality built into it, although eliminating those features can reduce your up front cost.

 

[Dcpcooks]

I have a buckeye hydro unit. $252 shipped with 75 gpd, tds meter, pressure gauge. Auto shut off, chloramine block and all the hardware needed to hook it up. It's been a champ for 16 months. It's finally time to replace all the cartridges.

Give Russ a call you'll be happy and you won't need to lug water around anymore

 

[augiedoggy]

I have one just this...
http://www.ebay.com/itm/Reef-Aquari...629327&hash=item2ef2d12c5d:g:RhYAAOSw~otWcFxF
Mine is a "max water" brand.
Bought about 8 years ago for about the same price for my reef tank. it came with the tds meter and guage and such. (The tds meter requires me to actually insert it into a cup of water to test which takes all of 20 seconds.) With regular water filter changes it works just as it should... The TDS meter shows it removes all but a couple ppm..(original water has 300-400ppm)
mine came with 2 exit ports, one through the deionizer filter for my reef tank and one to bypass it for everything else.

There is nothing that I know of that makes one of these systems significantly better than another when using the same brand of filters... you want the pressure gauge for sure. Incoming pressure will directly impact the efficiency of the system. keep in mind for every gallon of RO water made about three more go directly down your drain...There are different efficiency claims by different membrane makers. I have no doubt that some of what they say is true. Its one of those types or things though that has no regulations to enforce any claims really... The water filter market is full of a lot of resellers and a lot of rebranding of the same generic products with different claims. A local copy machine dealership place in buffalo is also in this business and I laugh every time I pass their building with the dual sign..

If you think you will need support from the buyer then by all means spend more for it but its really a pretty simple device. I myself cant justify spending what some sellers are asking for the same quality device you can get for around $100.. just my 2 cents. The replacement filters are cheap. (again some are better than others and if anything this is more important than the brand of system but dont shop by price alone because the same filters are sold for drastically different prices with different branding.).. You can put whatever micron filters you want but keep in mind it will effect how long they are effective for and how effective the system is as a whole... its designed to work in stages for a reason. starting with 1 micron will likely mean you will be replacing that filter very often and causing a huge drop in water pressure which effect the membranes performance. obviously the amount of use it sees will effect your filter life as well.. I replace mine about every 6-8 months. The membrane lasts for years.

 

[ScrewyBrewer]

I like the membrane auto flush feature the best, the unit is smart enough to know when the membrane needs flushing to extend its useful life. The inline TDS meter provides readings both of incoming water as well as outgoing water. I haven't changed the TDS setting since hooking up the unit 3 years ago.

 

[augiedoggy]

I dont have an autoflush but I havent replaced the membrane since I got the system (or possibly on the first filter change) The TDS meter shows it still working correctly... huge difference in how the lactic acid adjusts the ph of RO vs non RO.. it takes very little to effect the RO vs tap water.
I usually use a mix of the two for my beer making since Ro has everything stripped from it and I dont like to rebuild for many styles... porters and stouts get straight tap water that sits with a camden tablet or 2.

After reading this though I decided to buy another membrane anyway since mine is pretty old just to be sure..

 

[brew703]

I went ahead and ordered the one from Bulk Reef Supply. I looked at several on EBay but never could get a reply from the seller or a sufficient answer to a few questions. Also by the time I order additional filters plus the manual flush I was close in cost to the BRS system. I also looked at the system from Buckeye Hydro but decided the BRS system was better for me.

I will have to order a pressure gauge and for the system I ordered I will change out the second stage filter for a 1 micron.

We'll see in a few days how it works.
Thanks for the replies.

 

[brew703]

Rec'd my RO system. Came from Bulk Reef Supply, 75 GPD 4 stage.
Set it up, checked for leaks and all is good. Ran for an hour per instructions.
70psi
Tap TDS= 192
RO TDS= 012

Does this seem correct?

 

[The_Bishop]

That's only 93-94% rejection. Not sure what RO element it comes with but most 75gpd membranes are rated for 99% rejection.

 

[brew703]

Its suppose to be a dow filmtec membrane.
I'll re-test it again later today.

 

[mabrungard]

Don't put too much faith in a TDS reading. They are crude instruments and a reading of 12 ppm sounds good to me. In addition, I find that some RO membranes improve their performance after a little break in.

 

[brew703]

Thanks for the replies everyone.

 

[mongoose33]

Whenever I start up my RO system, I need to run it for a few minutes to clear the lines and apparently, the filter. The initial 8 ounces or so of RO water it produces has a higher TDS reading than it has once it's settled down.

Did some yesterday. Initial reading was 12 ppm. But after letting it get going, I measured it again and had 6, which is as good as it ever does.

Run it for a few minutes, use a clean cup or receptacle to collect the water, and see if it improves. Does for me.

 

[The_Bishop]

Absolutely right. Also, rinse the cup with the permeate once or twice to insure that there isn't some residual stuff dried into the vessel that will change your reading.

 

[brew703]

I just got the system yesterday. I took a TDS sample from the same faucet I will be using and it was 194. I ran my system for an hour yesterday per instructions. After that hour I took a RO sample and it was 12. During that hour, probably produced 3-5 gallons of RO water.

I would think after running for an hour it would have been good to go.
I also used two different glasses, one for tap and one for ro.

Maybe 12 is good enough and that's what I should expect. I thought it would be closer to what the manufacturer specs state. Not going to be collecting any brewing water for two more weeks but will run the unit for few times in between to collect a few gallons for drinking etc. Hopefully in two weeks it will be closer to 98-99%, which is what Dow states.

 

[mabrungard]

Maybe 12 is good enough and that's what I should expect. I thought it would be closer to what the manufacturer specs state. Not going to be collecting any brewing water for two more weeks but will run the unit for few times in between to collect a few gallons for drinking etc. Hopefully in two weeks it will be closer to 98-99%, which is what Dow states.

Again, you are assuming that either of the TDS readings are correct and the membrane is faulty. I am happy with a reading of 12 ppm (of course my raw TDS is over 600 ppm). If you feel that its that important to get to the bottom of this, I suggest you send a samples of the raw and product water to Ward Labs for testing. It would provide an idea if the TDS readings are reasonably accurate (they aren't going to be since its a corollary with conductivity).

 

[brew703]

Again, you are assuming that either of the TDS readings are correct and the membrane is faulty. I am happy with a reading of 12 ppm (of course my raw TDS is over 600 ppm). If you feel that its that important to get to the bottom of this, I suggest you send a samples of the raw and product water to Ward Labs for testing. It would provide an idea if the TDS readings are reasonably accurate (they aren't going to be since its a corollary with conductivity).

I'm going to take your advice and be good with 12 ppm. This is my first RO system and I assumed I would be closer to 98-99% rejection.
And that's also assuming my TDS meter is accurate.

 

[brew703]

Again, you are assuming that either of the TDS readings are correct and the membrane is faulty. I am happy with a reading of 12 ppm (of course my raw TDS is over 600 ppm). If you feel that its that important to get to the bottom of this, I suggest you send a samples of the raw and product water to Ward Labs for testing. It would provide an idea if the TDS readings are reasonably accurate (they aren't going to be since its a corollary with conductivity).

Lets assume the TDS results both before and after filtration is accurate. Lets also assume the RO membrane is not faulty. What would cause a system to only get 94% rejection vs 99% rejection, which is what the manufacturer specs show? Does water temp play a part? I didn't check the water temp but would assume it's between 75-80 degrees.
Just curious as I've seen similar systems get closer to 99%.
Thanks.

 

[The_Bishop]

The pressure differential across the membrane, the water temperature, and the incoming water TDS all play big roles in the 'purity' of the permeate.

In Martin's case, with a starting TDS of 600, getting 12 is a 98% rejection rate. Without knowing the specifics of his system, that's still pretty good. In your case, you are starting with a TDS of 192. You *should* be seeing a permeate TDS between 2 and 4 if you're getting a 98-99% rejection.

Couple of things can cause a higher permeate TDS. Pressure differential across the membrane is one; are you using a pressurized storage tank? If so, as the pressure in the tank builds it increases back pressure on the membrane the the rejection rate suffers. Likewise, water temperature plays a role; if the water's warmer, it'll create permeate faster but it'll also have a higher TDS (Not at the rate you're seeing, though). What's your permeate:brine ratio? If it's not flushing enough that can cause an increase.

Other thing that might cause it? The membrane has two o-rings at the bottom where it 'plugs' into the housing, as well as a larger top seal. If those are damaged you'll have cross-leakage that can cause a higher permeate TDS.

 

[brew703]

No storage tank. Not sure what the permeate:brine ratio is. How is that determined?
I didn't pull the RO membrane out- guess I could check it but it's a new system that came put together.

 

[jayrome2722]

I just bought an APEC system on Amazon. Made my first beer with it 2 weeks ago, so we'll see. I have a ton of iron in my water, the RO water tastes great. I keep a jug of it in the fridge for drinking at all times. You won't regret it

 

[The_Bishop]

The permeate:brine ratio is a measurement of volumes of permeate produced and the volume of 'waste' water down the drain.

So if you get one gallon of permeate and in making that gallon 4 gallons goes out as 'waste' you have a 4:1 ratio.

 

[brew703]

The permeate:brine ratio is a measurement of volumes of permeate produced and the volume of 'waste' water down the drain.

So if you get one gallon of permeate and in making that gallon 4 gallons goes out as 'waste' you have a 4:1 ratio.

I ran the system for an hour yesterday and I felt it produced more than one gallon permeate per hour. Didn't really pay much attn. If I had to guess, probably produced 2-3 gallons per hour.

I'll check it tomorrow. Is it best to produce less permeate per hour than waste? Would that translate to a higher rejection rate?

 

[The_Bishop]

I was using the 1 gallon strictly as a reference point.

You will always produce less permeate than brine; it's how the membranes stay alive. The 'waste' is actually flushing the surface of the membrane, preventing calcium precipitate (among other things) from fouling it.

The amount of 'flush' needed is highly dependent on the incoming water. Most residential systems are set up as 4:1 brineermeate ratio. If you're feeding the membrane softened water that's very low in calcium and magnesium. you can get away with a lower ratio. My system is running at a 2:1, but I'm feeding my membrane softened water and I constantly monitor the TDS.

 

[MaxStout]

My Buckeye system (75gpd) produces roughly 2:1 waste/permeate, which I consider very acceptable. I'm feeding soft water into the system. With hard water YMMV. I have the unit mounted over my big laundry sink and run the waste down the drain. The permeate yield varies by temp, with it being a bit lower in winter when the tap water is colder (and higher viscosity). Even then, the yield is around 2.5 gal/hour.

 

[brew703]

I didn't have a chance to run the system yesterday but will do so today.
I have no water softener- just straight tap. I did check the water temp and it was 82 degrees. I'll report back this afternoon.

 

[augiedoggy]

Rec'd my RO system. Came from Bulk Reef Supply, 75 GPD 4 stage.
Set it up, checked for leaks and all is good. Ran for an hour per instructions.
70psi
Tap TDS= 192
RO TDS= 012

Does this seem correct?

Seems like there's a bit more getting through your system than mine but then again mine is a five and six stage depending on where I draw the water from and you're using a different TDS meter than I am which will likely make a bit of a difference.

 

[brew703]

The TDS meter I use is an inexpensive one from Amazon. I was thinking about getting an inline meter but not sure if I want to go that route. At this point I assume it's accurate.

Also, not sure if I will keep the current filter set up- I may change out stage 2 to a 1 micron and either change the stage 3 to a .5 micron carbon block or leave as is (currently it's a 1 micron carbon block).

 

[brew703]

Ran my system yesterday. Here's some info:
Water temp: 82 degrees
PSI: 70
2.5 gallons of RO Water to 4 gallons waste water
Took approx 30 minutes to gather
TDS Faucet: 194
TDS RO: 11
RO rejection rate: 94.33%

I think my water temp is playing a part in the rejection rate. Kinda disappointed but appears to be normal. I'll recheck when it cools off down here.

 

[Buckeye_Hydro]

With your recovery cranked up so high (2.5/(2.5+4))=38%, you should expect rejection lower than factory spec.

If rejection is critical to you, I'd lower your recovery (i.e., use a flow restrictor that allows more concentrate flow). If you're using a Filmtec membrane, remember those membranes are spec'ed at 15% recovery. Based on our test data I'd expect you'd see about a 1% improvement in rejection if you went to 15% recovery.

About half of the time we get customers calling in with rejection rate issues, the root of the problem ends up being erroneous TDS readings: TDS creep not being accounted for, dirty sample containers, taking readings after a pressure tank, etc, etc.

Russ

 

[brew703]

With your recovery cranked up so high (2.5/(2.5+4))=38%, you should expect rejection lower than factory spec.

If rejection is critical to you, I'd lower your recovery (i.e., use a flow restrictor that allows more concentrate flow). If you're using a Filmtec membrane, remember those membranes are spec'ed at 15% recovery. Based on our test data I'd expect you'd see about a 1% improvement in rejection if you went to 15% recovery.

About half of the time we get customers calling in with rejection rate issues, the root of the problem ends up being erroneous TDS readings: TDS creep not being accounted for, dirty sample containers, taking readings after a pressure tank, etc, etc.

Russ

Thanks for the info. Rejection isn't that critical as long as my system is doing it's job. I am using a Filmtec 75 GPD membrane with a 550mL flow restrictor.
I gathered some brewing water yesterday and the rejection rate was right at 95%.
And it could also be an erroneous TDS reading. I'm using an inexpensive meter which i assume is accurate. But it's been consistent since I got the system & meter so that leads me to believe it's accurate.

 

[Buckeye_Hydro]

The 550 flow restrictor on your high pressure (20 psi over spec) warm (5 degrees F over spec) feedwater is what is over-restricting the concentrate and skewing the recovery.

 

[bumstigedy]

Is there a unit I can hookup to my garden hose faucet outside?

 

[Buckeye_Hydro]

Nearly any RO system can be hooked up so that it it fed from a hose bib. You can use a hose bib slipper, and a hose bib adapter to attach the feedwater line to the hose bib.

Because much of the residential scale systems are plastic on one sort or another, you don't want the system in the sun.

Russ

 

[brew703]

The 550 flow restrictor on your high pressure (20 psi over spec) warm (5 degrees F over spec) feedwater is what is over-restricting the concentrate and skewing the recovery.

If I replace the flow restrictor with another, whichever you recommend, would i expect a 1% increase as you noted earlier? If so, would that really make a difference in the quality of water?

You mention 20psi over spec, are you referring to the 70 psi i mentioned in a previous post? Same with the temp? The temps this past weekend, when i gathered the water was around 45 degrees. I didn't think to check the water temp but if i had to guess it would have been in the 60 degree range. And the rejection rate was maybe 1% better than the last time i checked it.

 

[Buckeye_Hydro]

Yes - if you use a flow restrictor that gets you closer to a 20% recovery, your rejection would improve a bit. Is that a big deal in your case? Maybe not - but you would know better than I. I don't think that is going to change any of your calculations.

Yes - your membrane is spec'ed at 50 psi and 77F. You mentioned having have higher pressure, and higher temperature.

Colder water will yield higher rejection, BTW.

Russ

 

[brew703]

Yes - if you use a flow restrictor that gets you closer to a 20% recovery, your rejection would improve a bit. Is that a big deal in your case? Maybe not - but you would know better than I. I don't think that is going to change any of your calculations.

Yes - your membrane is spec'ed at 50 psi and 77F. You mentioned having have higher pressure, and higher temperature.

Colder water will yield higher rejection, BTW.

Russ

I did read about the specs someplace. Didn't really think about water temp effecting rejection rate and I figured 70PSI would be ok.

With the cooler temps this past weekend, I figured rejection would be higher. Winter temps usually stay in the 40's with an occasional dip below that. Summer it's bad-- 80+ degree water temp so i figured rejection would suffer some.
I may try a different flow restrictor and see how that works out. Then again, I'm no expert but I don't see a 1% increase making a noticeable difference in water quality.

Guess I just have to accept what it is and roll with it. Thanks for the info.

 

[bumstigedy]

Nearly any RO system can be hooked up so that it it fed from a hose bib. You can use a hose bib slipper, and a hose bib adapter to attach the feedwater line to the hose bib.



Because much of the residential scale systems are plastic on one sort or another, you don't want the system in the sun.



Russ

Thanks. One additional question: Would occasional use of an to system be a problem? I would plan to store it in my garage and hook it up outside once a month when I brew.