how long do rodi filter last

[AZDesertRat]

Most drinking water systems use 10 micron or maybe 5 micron sediment filters and only nominal rated, which are about as effective as a screen door at protecting the billions of tiny pores in the cabon block which remove chlorine and volatile organics like herbicides, pesticides and fuel byproducts. A reef quality system uses a 1 micron or prefferably a 0.5 or even 0.2 micron and absolutely rated not nominal rated sediment filter so it protects the carbons pores so it can do its job of protecting the RO membrane.
Many drinking water systems still use granular activated carbon which truth be told lasts about 300 total gallons (60 treated and 240 waste gallons at 4:1 waste ratio). Others use 5 or 10 micron carbons which last a maximum of 6,000 to maybe 9,000 total gallons (again 1,200 to 1,500 treated gallons and 4,800 to 7,500 waste gallons) while a real reef quality system will use a SINGLE 1 micron or better yet 0.6 or 0.5 micron near absolute rated carbon block which lasts longer and filters better leading to a lower cost of ownership and longer RO membrane life.

Drinking water membranes can be 90% efficient or rejection rate and thats OK since TDS is not an issue with drinking water. Ree fsystems should use at least a 98% rejection rate and treated and tested membranes are bette rthan off the shelf dry untested and non guaranteed membranes as you just purchased. As I said before a 1 or 2% increase in efficiency can mean hundreds of dollars over the life of the membrane.

 

[greg0385]

Well all the filters came from brs and so shouldnt they be reef filters. I dont know what micron as i didnt read the label as they came from a local reef friend who i had helped and this was the way he paid me to help him. I did email the seller of the membrane to see if it is possible to cancel the purchase in hopes to purchase your advised membrane.

 

[AZDesertRat]

BRS doesn't sell anything more fine than a 5 micron sediment filter and they don't say if its nominal or absolute so its probably nominal since absolute costs more money and a vendor would want to tell you if its better and why it costs more.
You might not know, you can see 40 microns with the unaided human eye so 5 microns is still pretty coarse. 1 micron is many times smaller and the better 0.5 microns absolute is several times better and only like $12. By going with a better sediment filter you only need one good carbon block since it is being protected by the sediment filter and will easily last longer than the 6 month recommended replacement timeframe if monitor pressure drop with a properly placed pressure gauge between the carbon block and the RO membrane where it should be.

 

[kgreenjinx]

+1 to the co2 killing do resin. I am on a well with 40 tds at the tap. But high co2. I have been battling this for 8 months. I get about 80 gallons of Di before I hit 1 tds. I need to order a degasser. For now I buy bulk Di resin and change often. I recharged a couple times but it was not worth it. I also use a booster pump. Definately worth the $100 bucks.

 

[turfster26]

BRS doesn't sell anything more fine than a 5 micron sediment filter and they don't say if its nominal or absolute so its probably nominal since absolute costs more money and a vendor would want to tell you if its better and why it costs more.
You might not know, you can see 40 microns with the unaided human eye so 5 microns is still pretty coarse. 1 micron is many times smaller and the better 0.5 microns absolute is several times better and only like $12. By going with a better sediment filter you only need one good carbon block since it is being protected by the sediment filter and will easily last longer than the 6 month recommended replacement timeframe if monitor pressure drop with a properly placed pressure gauge between the carbon block and the RO membrane where it should be.

What micron do you run on your sediment and carbon?

Also, I want to eliminate having my topoff hooked directly to my ro/di system due to the creep factor. How can I properly run my topoff? I was thinking of having my ro/di make 40gls at a time in my rubbermaid container. How can I properly pump and/or preasurize my 1/4" topoff line to feed my sump?

And I think you are correct....I have an old (6+ years old) Abundant Water ro/di setup and I think I may try SpectraPure. Arn't most ro/di hardware pretty much the same? Does it only come down to what filters and membrane you are running. Most of the ro/di system is just 10" plastic housings and 1/4" tubing, etc. I have made substantial upgrades over the years with my Abundant Water system, so it does have most if not all of the nicer features now.

MANY THX and GREAT TOPIC.........

 

[greg0385]

^^^this gives me hope if i buy a good membrane and filters with a booster i may be able to make more water with less filter purchases.

 

[AZDesertRat]

Components can vary in quality as much as filter cartridges or membranes. Look for housings that are ANSI/NSF and UPC rated which means they have been subjected to rigorous testing by independent testing labs and are both safe under pressure and constructed out of materials suitable for contact with drinking water. Many lower end units have cheap imported knockoffs that visibly look the same but are not. Some Chinese plastics contain lead above permissible levels for one example or thye plastic becomes brittle and cracks with the slightest wate rhammer or pressure spike.

Look for fittings such as John Guest speed fittings or Pur Loc which are both name brands and again are tested and approved. They are push in type fittings as opposed to the old style compression fittings with screw on nuts.

Some units use flimsy plastic brackets, others use powder coated steel or aluminum brackets or heavier reinforced plastic brackets. I prefer units with capillary tube type flow restrictors so you the end user can trim it to fit your unique water conditions instead of the supposedly "one size fits all" fixed flow restrictors that are never quite right and can eithe rwaste too much water or worse ywt not enough and ruin a membrane with too little waste ratio.

Myself, I use a 0.2 micron absolute rated pleated sediment filter with 10x the surface area of a normal poly filter. This not only filters much better but the extra surface area means it has less pressure drop or head loss so the membrane works better. I then use a single 0.5 micron 20,000 gallon carbon block and a 90 GPD Select series hand tested and guaranteed better than 98% rejection rate RO membrane. Mine has averaged 99.23 to 99.35% rejection since day one almost 2.5 years ago. My system is the Spectrapure MaxCap UHE ultra low waste system and is running at 95 psi and slightly less than 1:1 waste ratio as designed. I have only changed 3 MaxCap DI cartridges and 1 SilicaBuster DI cartridge since it was brand new so am getting about 1000 gallons per DI cartridge even with my high TDS, always over 530 and as high as 850 at times, and high CO2 present in Phoenix tap water.


For my ATO, I run the RO/DI in to a 23 gallon Rubbermaid recycling can which has float switches set 12" apart so it has to drop at least 11 gallons before the RO/DI starts again. This gives me nice long filter runs and reduces the effects of TDS creep since it does not start and stop frequently. From the ATO storage I have a Spectrapure UPLC II liquid level controller which uses a peristaltic pump to draw water from th ATO reservoir in the garage 35 feet away to the sump in the dining room. The UPLC is adjustable between 1/10" and 4" so I can set the level to what I want with the touch of a button and have it fill as frequent as I want or less frequently. Any powerhead can work as a ATO pump but I like the safety of the peristaltic pump on the UPLC since it cannot backsiphon due to the 3 lobe roller design plus can be adjusted in 10 different flow rates so it could be impossible to overfill the sump even if I wanted to.

 

[Reef lvr]

If your IN probe is on the tap water side it needs to be moved to the RO side and inserted into a plastic John Guest tee like they come standard with. Also make sure the probeis rotated the correct direction as shown in the instructions that come with the TDS meter.

If your tap water TDS is only 16 and you are still only getting 90 gallons out of a DI refill then you may have a bad membrane. Move the meter to the correct position and check the RO TDS. You more than likely do have a CO2 problem and you can check that with a CO2 test kit Spectrapure makes and sells pretty inexpensive. I am somewhat biased towards Spectrapure products but it is because I have owned and tried all the others and there really is no comparison. They treat and test all the RO membranes and its usually 1 to 2% or greater more efficient than any other on the market bar none. That is important since a 2% increase in efficiency doubles the life of your DI resin without doing anything else. Add to that they blend all their own DI resins based on thousands of hours of testing under the worst conditions imaginable so they last anywhere from 30% to 400% longer than any other resin available in the hobby. Their research pays off big time.

+1 you will save money in the long run with buying a Spectrapure, i had a cheap one before and had to replace the Di and filters often. I bought the Maxpure 10-12 months ago and with tap TDS at 380-420 my Di is maybe 30 percent spent after a few thousand gal.

 

[turfster26]

Components can vary in quality as much as filter cartridges or membranes. Look for housings that are ANSI/NSF and UPC rated which means they have been subjected to rigorous testing by independent testing labs and are both safe under pressure and constructed out of materials suitable for contact with drinking water. Many lower end units have cheap imported knockoffs that visibly look the same but are not. Some Chinese plastics contain lead above permissible levels for one example or thye plastic becomes brittle and cracks with the slightest wate rhammer or pressure spike.

Thank you for your very detail response to my questions.

I did look and you are correct. I am using 5 micron (nominal) sediment and carbon filters. And I am using BRS DI resin.

I also did a quick test. I am using a 100gpm membrane and it is exactly 3.5 years old. I am using an HM Digital DM-2 inline meter to check my TDS on both my Ro and DI. My incoming water is at 130-150 TDS and my TDS out of the RO is 5 TDS. Is my membrane and/or filters preforming well? If my math is correct I am at a 97% rejection rate?

I did a good psychical inspection and my entire unit looks to be in very good shape overall. I do run my household drinking water off the RO portion of the unit too. Assuming that my unit is in good shape, should I simply upgrade my sediment and carbon filters? And install a SpectraPure 90gpm membrane. Or should I simply take advantage of SprectraPure scratch & dent/refurb model and turn my current Abundant Water unit into strictly a household drinking water unit and remove the DI cartridge?

Lastly, I need to find a better solution to my ATO because right now my LifeReef ATO is plumbed directly into my RO/DI unit and I am burning through DI resin at a good clip. I will have to look into the SpectraPure ATO liquid level controller.

And, many thanks for all your help.........

 

[AZDesertRat]

I found when I converted my Watts Premier to a reef type system it cost me much more than if I had bought a good system to begin with. That was over 15 years ago and reef systems were not as plentiful or as affodrable as they are today but it still holds true if not moreso. Look at the cost of a new membrane and flow restrictor ($39-$44) and a new sediment, carbon and DI ($52), thats almost $100 right there. The MPDI on sale is $120 and comes with all the best components and new filters plus has a guarantee.

I personally have a seperate system for our drinking water so I don't have to seperate the RO from the RO/DI. I hope you are not using water stored in the pressure tank to make the DI water? If so thats a really bad idea since the pressure tank stores and concentrates TDS from the frequent starts and stops a pressure tank experiences, another reason for short DI life. Way back when I did this very thing I added a second pressure tank so I could get 6.6 gallons of pressurized water and this helped the TDS creep a little but still wasn't satisfied so I installed a 14 gallon pressure tank and still had the TDS issue. I eventually isolated the pressure tank strictly for drinking and ice maker via a check valve and used RO straight from the membrane to make my DI and my TDS and short DI life improved. Today I scrapped all that and have seperate systems and its so much simpler.

 

[turfster26]

I found when I converted my Watts Premier to a reef type system it cost me much more than if I had bought a good system to begin with. That was over 15 years ago and reef systems were not as plentiful or as affodrable as they are today but it still holds true if not moreso. Look at the cost of a new membrane and flow restrictor ($39-$44) and a new sediment, carbon and DI ($52), thats almost $100 right there. The MPDI on sale is $120 and comes with all the best components and new filters plus has a guarantee.

I personally have a seperate system for our drinking water so I don't have to seperate the RO from the RO/DI. I hope you are not using water stored in the pressure tank to make the DI water? If so thats a really bad idea since the pressure tank stores and concentrates TDS from the frequent starts and stops a pressure tank experiences, another reason for short DI life. Way back when I did this very thing I added a second pressure tank so I could get 6.6 gallons of pressurized water and this helped the TDS creep a little but still wasn't satisfied so I installed a 14 gallon pressure tank and still had the TDS issue. I eventually isolated the pressure tank strictly for drinking and ice maker via a check valve and used RO straight from the membrane to make my DI and my TDS and short DI life improved. Today I scrapped all that and have seperate systems and its so much simpler.

Yes, I did have them installed together and ran the pressure tank with the ATO, but I did separate them about 1.5 years ago.

I think you are correct, $120 for a new RO/DI dedicated strictly for ATO and making fresh saltwater is the way to go. As stated, my existing RO/DI unit is well over 6 years old and it is time to dedicate that to drinking and get an entirely new setup for my reef tank.

Now as I have to do is figure out how I can configure an ATO from my 44gl Brute drum so I can make fresh DI water and only run the RO/DI unit for large quantities to eliminate the "creep factor" and allow my DI resin to last much longer.

Two more questions. Is running my DI at 1-2 TDS that bad for my SPS tank? And, how can I calibrate and/or make sure my handheld TDS meter is accurate? My inline DM-2 states that I have only 1 TDS; while my handheld is reading 4 TDS. Are there more accurate handheld models or manufacturers?

Many thanks again.....you have been a GREAT resource.

 

[AZDesertRat]

I would trust the handheld meter since it is temperature compensated and the inlines are not even though they claim to be. They actually sense air temperature and not water temperature which are rarely the same and it can be off as much as 2% for every degree C the temps differ.

You can get calibration solutions for TDS meters from anywhere that sells meters. Buckeye Field Supply and Spectrapure both sell them. I use a HM Digital COM-100 handheld as its one of the few hobbyist grade meters that reads down to tenths or a ppm and can be calibrated in several different ways. The HM Tds-3 and TDS-4TM are also good meters with built in digital thermometers too like the COM-100 only read in whole numbers not tenths.

As for making larger, less frequent batches, you can install float switches and a solenoid valve, Spectrapure sells a complete kit, or you can just fill the Brute full then shut the RO/DI off manually for several days or a week or whatever until it drops then turn it back on again. As long as you remember to turn it on!