3 stage RO question

Jim_S

Timo Boll
I've been given a 3 stage RO from a local club member. I don't know much about the unit, but I imagine I am going to have to replace the filters and membrane (I will test the TDS first of course).

Anyways, I'm going to add on a DI unit from buckeye, but I want to make sure I get good filters to keep the membrane and DI from getting used up quickly.

What would be the best arrangement?

I was thinking 10 micron filter, then 5 micron carbon block? Then 75gpd membrane? Is there a better combo that I should use?

TIA!

Jim
 
Best?
IMO. (1) High flow- Zeta Zorb 0.2 micron absolute sediment > (2) 0.6 Matrikx +1 Carbon 20,000 chlorine guzzler > (3) Spectra pure 90 Gpd 98% + membrane.

(I put a 1 micron sediment before the Zeta Zorb 0.2 sediment. some waters have more sediment than others. )

The price of the Spectra pure 98% +membranes are a little too pricey for me. I would only consider using them if your Tap TDS is VERY high or you use a lot of water. Then you could recoup the extra expense by saving on DI expenses.
 
The purpose of the prefilter and carbon block is to protect the more expensive RO membrane which is the workhorse of the system. You want to install the best filters you can to accomplish this. I too use the 0.2 micron prefilter and a 0.5 micron Chlorine Guzzler. I would disagree with Roland though and do recommend the Spectrapure Select hand tested membrane to everyone. Over the life of the membrane, no matter how good or bad your tap water is, you will realize a cost savings. In my case it was less than a year to see the return on my investment.
I saw an increase in DI resin life from 150 gallons per 20 oz. refill/cartridge to 630+ gallons per refill/cartridge immediately. The difference amounted to replacing a DI cartridge every other month to replacing it twice in an 18 month period. Big savings.
 
Thanks guys!

Okay, so it should go:

.2 micron filter -> .5 micron chlorine guzzler -> (90 gpd spectra pure??) -> DI unit.

Does that sound right?

I'm just a little confused about the membrane. Roland recommended the spectrapure, the A.J. disagreed.... Is the spectra pure select 90 gpd the right way to go?
 
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<a href=showthread.php?s=&postid=11997535#post11997535 target=_blank>Originally posted</a> by rbursek
Look at A J's occupation and you decide!

:lol:

Yeah, for sure!! Dude knows his stuff.

I'm just confused at his response. It appears that he disagrees, then recommends the same thing, so I just want to make sure I understand what he's saying :)


Oh yeah, one more question:

Is there a vendor that sells all the mentioned components so that I can get it all in one stop?
 
The only part I disagreed with was not recommending them to everyone. Roland says he only recommends them to certain people, I say everyone will benefit from them.
Off the shelf membranes have no guarantee as to their efficiency or their delivery rate (GPD). No other manufacturer guarantees the effectiveness of their membranes so what you get is what you get. The reason I recommend these membranes is very easy to justify. It is well known for every 2% you increase the efficiency of the RO membrane you DOUBLE the life of your DI resin. This is using standard off the shelf mixed bed DI resins. You will also find Spectrapure is the only company that custom hand blends every bit of resin that leaves their facility. They bench and beta test resins on a daily basis and use only the best resins blended to get maximum life and superior quality water.

Before doing anything i would get my hands on a good handheld TDS meter and test both the tap wate rTDS and the RO only TDS from the unit. Chances are if it has been setting for any length of time it will need both the prefilter and carbon block replaced and if the membrane has been allowed to dry out it probably needs replacing too. If it was stored wet it may still be OK at this point but only the meter will be able to tell you this.
 
Thanks A.J.!

Yeah, I'm picking the unit up tonight, but have a feeing that its been stored dry. I will test it as soon as I get it hooked up, and go from there.
 
Those Spectrapures are alot, $100 just for the membrane? time you buy that and all the other stuff you will be at the same price as my brand new 5 stage with dual TDS unit.

There are some other really good unit to me.

Its like saying you have to buy a Bubble king skimmer. its the best so why settle for something else? Even though there are other skimmers that do a great job


just my opinion
 
<a href=showthread.php?s=&postid=11997398#post11997398 target=_blank>Originally posted</a> by AZDesertRat
The difference amounted to replacing a DI cartridge every other month to replacing it twice in an 18 month period. Big savings.

The SP Select membrane will prolong the Life of your DI.

By SP literature I was under the impression that it would give you 200% more DI life not 800% more like AJ is getting.

I will definitely agree that if the Select membrane, by itself, prolongs the DI life 800% then it is worth the extra $55.

AJ, do you think their might be other things influencing the life of your DI? You might have made some changes to your RO at the same time. The new 0.2 Zeta Zorb prefilter and the Max Cap Di may also be influencing your DI life. Which may account for the % of life.

What improvement should we expect to get form the SP Select membrane by itself?

This is the way i understand it. If the average Dow Filmtec 75 GPD membrane gets 97% rejection and the Spectra pure Select gets 99%.

100 tds goes down to 3 PPM TDS
100 tds goes down to 1 PPM TDS

This to me, means it should be about 200% better, As far as TDS goes.
 
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Davey, you're right. After all the new components, I'm right around $140+shipping.

I might as well just get the typhoon III.
 
<a href=showthread.php?s=&postid=11997398#post11997398 target=_blank>Originally posted</a> by AZDesertRat

I saw an increase in DI resin life from 150 gallons per 20 oz. refill/cartridge to 630+ gallons per refill/cartridge immediately.

The difference amounted to replacing a DI cartridge every other month to replacing it twice in an 18 month period. Big savings.

Sorry, i skipped the 150 to 630 which is closer to 300% better. which makes since to me.


Jimdog
IMO, It boils down to which RODI (or parts) is best for you. That is based on how much water you use and what your tap water is like TDS...

AJ's tap is around 900 TDS. So it dose not take much water to recoup saving of a great quality RO unit Like the Max Cap RODI(SP)

My Tap is 30 TDS, but i use a lot of water. I use a Water Saver RODI (simular to thefilterguys) it saves me over $100 (20,000+ gallons & prefilters...) a year.

kdblove_99, May have low tds and low water use, so the normal or budget RODI may be best for him.
 
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You will not get the same performance out of any other membrane guaranteed. The averge off the shelf membrane tests out closer to 96% in almost all cases. Spectrapure fails many more membranes than they pass during their testing process. They also ship all membranes, even their non Select series in a proprietary pickling solution to improve ther performance unlike any others too. All other vendors ship membranes dry.
My MaxCap averaged between 99.23% and 99.35% rejection for the 18 months I used it, thats both as a 90 GPD single membrane system and after I upgraded it to a dual membrane system capable of 240 GPD (90 GPD and 150 GPD Select membranes).

The Typhoon might be a lot cheaper but it will not perform the same I guarantee you. Get a TDS meter, take the readings then figure out how much water you think you will be making for both water changes and top offs.

My tap water TDS was a consistent 800-835 during the entire 18 months. With my Typhoon III configuration, (10 micron sediment, 5 micron carbon, 1 micron carbon and off the shelf 75 GPD Dow Filmtec RO membrane my RO only TDS averaged 13 to 15.
With the Spectrapure configuration, 0.5 micron or later the 0.2 micron prefilter, a single 0.5 micron Matrix Chlorine Guzzler carbon block and the 90 GPD Select hand tested membrane, later with both the 90 and 150 GPD Select membranes my TDS went from 13-15 to 5.3-6.2 using a calibrated COM-100 TDS meter and a Thornton Benchtop conductivity/resistivity meter both.

Normal mixed bed DI resin was used with the old 75 GPD system and it never ever lasted more than 150 gallons before showing a TDS of 1 or higher. The MaxCap system used a MaxCap cartridge as a roughing or pre DI filter and a SilicaBuster as the final DI. In 18 months I changed the MaxCap twice, once at 630 gallons and again at about 1450 gallons. The SilicaBuster had never been changed during that entire period and I was still getting a true 0 TDS, (18+ megaohms) when I sold the unit complete. It had right at 2000 gallons through the DI system and the second replacement MaxCap cartridge was still going strong along with the SilicaBuster.

Spectrapure says you can expect 3.5x the DI life with the MaxCap but I found it to be better than that in my own documented testing.

The prefilter and carbon block have very little if any effect on TDS, they are there to trap the big stuff of TSS, Total Suspended Solids not TDS, Total Dissolved Solids. You may see a very improvement but not much.

With the average TDS nationwide around 250 and much higher in parts of the country like the Southwest and LA area its well worth the investment. A TDS of 30 like Roland has is extremely rare and not the norm at all. We all wish we had his water for sure!
 
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