The Truth About Air Injection Iron Filters

The Truth About Air Injection Iron Filters
By Mark Timmons
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The Truth About Air Injection Iron Filters

It seems that these days everyone in the water treatment business is selling an air-injection iron filter.  They market these as "chemical-free iron filters" and some do work... at least for a few weeks or months, unless you have high iron.  Then they may fail sooner.  If you have "low to moderate" iron, they may work for a while, but many are doomed to failure in the long-term.  Maybe, I should have called this "WHY US WATER SYSTEMS DOES NOT SELL AIR INJECTION IRON FILTERS." But, before we discuss why they are doomed, let me explain how they work:
  • Companies who build these "air-injection iron filters" utilize a water softener control which used a "nozzle and venturi" assembly (commonly called and "eductor" or "injector") which creates a vacuum that is used to draw salt water (commonly called brine) into a media tank (usually containing cation-exchange softening resin);
  • Instead of resin in the tank, these companies utilize media like Birm, Filox, Katalox, Pyrolox or Catalytic Carbon which provide an area for iron to oxidize; and
  • Instead of brine, the water softener valve draws air (which contains oxygen) into the media tank where it oxidizes the iron (allegedly).
That's how it works and it really sounds great, doesn't it?  However, like anything it is not all 100% true.  In fact, it may not even be 50% true.  Here's the problem:  to remove iron, it has to be oxidized - 100% oxidized!   The iron is not fully oxidized and it forms a tremendous amount of "iron sludge."  This sludge fouls the media, coats the surfaces and plugs the injector so that it can no longer draw air through its eductor.  Then, the iron that has accumulated in the media and internal parts (and plugged the injector) continues to build up.  The system is overwhelmed with iron sludge and ceases to work. If you think I am making this up, check out this picture that was taken in an actual application after one year on just 2 ppm of iron: [caption id="attachment_6380" align="alignleft" width="225"] Huge amounts of iron sludge of gloves from distributor tube.[/caption] Here's what happens, oxidizing iron with air containing about 20% oxygen leaves a great deal of iron sludge behind around the the top of the tank, the value and the distributor, as well as the media itself becomes overwhelmed by the sludge.  Within a few months, the eductor (injector) is plugged with iron sludge and the water softener control value quits drawing air.  It does nothing.  The iron continues to build up and soon thereafter, the system is overwhelmed.  Sometimes it simply shuts down from sludge and the flow is greatly impacted. Most of the time, you just start noticing iron stains and by the time you do something about it, it's too late. There's one way to make sure your air injection system doesn't stop working and that is to disassemble the valve every 3-6 months, clean the parts with chlorine or sodium hydrosulfite and sodium metabisulfite, being sure to clean the injector assembly so as to allow it to function properly. It's probably a good idea to clean out the media with chlorine or sodium hydrosulfite and sodium metabisulfite as well. Now, if that seems like a lot of work, it is.  So, some customers just add on a room and let their local water treatment company technician live there (OK, that's just sarcasm, but you get my drift). So, what is the solution?  It's simple for us - we use H2O2 instead of Oxygen - It's a much better oxidizer than oxygen and it doesn't require that a service technician move in with you.  Hydrogen Peroxide works every time and since it is such a great oxidizer, it does not leave all that iron sludge to clean up and there are no injectors to plug. We sell systems all over the world.  We sell direct and eliminate-the-middlemen, so we can't send out a service tech every time you have a problem.  I know that people are going to write in and say that they have an air-injection iron removal system and it works, but they don't work enough of the time that we can promise it will remove the iron or sulfur.  We can make that promise with hydrogen peroxide.  It works EVERY TIME.  No kidding around. Check out our inFusion Systems  if you want to eradicate iron and sulfur. NOTE:  This post has been updated.  The revision changes EVERYTHING! Find the update HERE.
December 27, 2018
Comments
Les
March 22, 2018 at 1:36 PM
Mark- Nice analysis on a common problem. I appreciate your humor, too. But I am looking for a rust removal system for a well-sourced water supply (Florida coast) lawn irrigation application. The OXi-Gen Systemc will cost more than I am willing to spend. I guess I’ll have to resort to periodic power washing of the fence and house exterior unless you have another idea. Note: Well is not used for household use. thanks.
Mark Timmons
March 22, 2018 at 4:40 PM
Les, You have to weigh the cost and if it is too much, I get that! Frequently, the chemicals you have to use to clean off rust can have a deleterious effect on them...
Stan
June 6, 2018 at 7:21 PM
I bought one of these air injection systems (from US Water mind you) and my valve looked like the picture above in 8 months. By the time I called tech support they had discontinued the sales of air injection system for this very reason - a lot of customer call backs apparently. I was frustrated at first but came to understand the product did not fail, it simply required more maintenance than I was willing to give. To US Water's credit they were quick to understand the situation and get me upgraded to peroxide injection for under $1,000. The change was quick and easy for anyone who can work with pex or copper. Haven't had any problems since. First impressions on USWater - knowledgeable - helpful. Just wish I would have bought the peroxide system first time around and saved myself some time. Also to speak to your point about a higher pressure backwash... this would require upgrading a well pump for some folks and that is just a whole other can of worms. That wasn't in the cards for me so peroxide injection was the most cost effective route in my case.
Mark Timmons
June 7, 2018 at 3:40 PM
Air injection can work, but it requires a lot of maintenance. H2O2 ALWAYS works!
Ed
August 22, 2018 at 10:04 AM
I'm wondering how expensive is the H202 and what would be the aproximate rate of use?
Mark Timmons
August 22, 2018 at 12:49 PM
The average family spend $200 to $300 a year on H2O2. If you area "<em>glass half empty person</em>" you might think that is just an unnecessary expense. But, if you are a "<em>glass half full person</em>" you might think that is a small price to pay for awesome water. It depends upon your perspective.
Les
September 8, 2018 at 10:39 PM
Thanks for the informative blog. As always there are more than one way to skin a cat...I am here because I have been using air injection for years now, but it is not with out a fair bit of maintenance. Replacing media beds in my tanks is required about every 2 years. I've gone past 2 years, but then I have more to clean out. The system was originally designed such that the Venturi drew air before my preasure tank, it then went thru a coil of 100 feet of 1 inch water line (gave the air time to turn the iron into a solid), then into a filter bed. Within 2-3 years, the 100 feet of hose would almost become blocked completely. I Do not advise this nonsense. I am building a new home and want to come up with a better solution. Perhaps go with the peroxide injection or change out the 100 feet of hose with a holding tank of sorts that won't clog, something similar to what Jorge used, just not aeration. Your thoughts.. Also, I had a someone tell me they had iron problems in their well. They started dumping a pail of hydrogen peroxide down the well periodically, and that they can't believe how good it works. My thoughts there are that all of that iron is now collecting on the bottom of the well. Can't be a good thing??
Mark Timmons
September 9, 2018 at 10:54 AM
Pouring H2O2 down the well is counter-productive. That's not how the process works. H2O2 is simply much better than O2 and don't use that 100 foot coil. Maintenance is almost ZERO. The media typically gets replaced every 5 years or so. That said, you need a detailed water test, like this: https://www.uswatersystems.com/us-water-lab-water-test.html Once we know exactly what is in the water, and at what levels and if there are competing contaminants, the we can tell you if H2O2 is right for you... or if there is a better solution.
Clifford Giebelhaus
November 16, 2018 at 1:32 AM
I am tired of maintaining my pressurized air injector system. It is placed right before the pressure tank. The rust filter is after the pressure tank. There is no water softener in the system. We have a farm well. Over 2 1/2 - 3 years the pressure tank, line from pressure tank to rust buster cylinder and '5 in 1' media bed inside cylinder are all pretty much plugged. The house water flow decreases to the point where its only one tap at a time and nobody uses an outlet or toilet when someone's in the shower. The backwash system is working fine. The system just sludges in over time. I would like to just go to a water softener only. My water specs are: 25 Hardness / 3.6 ppm Iron / 7.5 pH / 930 ppm Total Dissolved Solids 1) How many ppm of iron can a softener alone remove? 2) Would a softener only 'kill two birds with one stone' -- take care of the hardness AND iron? 3) Is there any validity to the statement 'a water softener's salt discharge will eventually wreck your farm house' septic tank by eating the concrete'? I appreciate any insight /comments you can provide.
Mark Timmons
November 19, 2018 at 11:30 PM
Salt does not harm concrete, unless it is expsed to it while frozen. In that case, it heats the surface and caused it to "pop." There are plenty of companies who will sell you a water softener that removes iron too... at least they say that. The truth is: <strong> That is pure fiction!</strong> At the pH your water is, you will not do a very good job of continually removing your levels of iron. You need this before the softener: https://www.uswatersystems.com/infusion-backwashing-filter-for-iron-sulfur-and-manganese-removal.html Feel free to call us at 800-608-8792 to get more info.
JoAnn Windisch
January 9, 2019 at 8:09 PM
When you have this air induction system is your water the color of milk? Culligan put one of these on my well and my water smalls bad and is the color of milk. They say that is normal. Is it
Mark Timmons
January 10, 2019 at 9:22 AM
Yes, it puts a lot of air in the water. If the glass sits for a minute, it should clear up.
Karlynn Zimlich
January 13, 2019 at 10:34 PM
I was thinking of getting an oxidation filtration system until I read your article. I have very hard water, a lot or iron and high alkalinity(9) which is leaving my plumbing and faucets with black build up inside. I also have the rotten egg smell (the smell decreased a bit by changing my water heater sacrificial anode). I have heard so much different advice that I am left completely overwhelmed! I followed the link for the equipment you suggested in a previous post but it is very expensive (https://www.uswatersystems.com/infusion-backwashing-filter-for-iron-sulfur-and-manganese-removal.html) Any advice?
Mark Timmons
January 17, 2019 at 6:51 PM
If you want to eradicate iron and/or sulfur, it is doubtful that an air injection filter will do that… especially after a few weeks. It is expensive, but in my life, I have found that cheap things aren’t good and good things are not cheap. We usually have some type of sale in place which can save you a few hundred dollars.
Fred Hemer
February 3, 2019 at 2:06 PM
So I have a question? Doc! It appears we are injecting peroxide before the the filter head ! So all the iron particles that are treated still pass thru the head ,what stops these participles from fouling the workings in the head! Because it appears they get filtered out after the head! Curious!!Seems the complaint with other systems is the fouling of the equipment This seems to have not changed here! What makes the infusions head impervious to fouling ??? Just asking Thanx! Fred
Mark Timmons
February 3, 2019 at 2:36 PM
Fred, That's a very good question. Hydrogen Peroxide is H2O2, while Oxygen is O2. When using oxygen alone, the oxidation process starts as soon as the oxygen touches the water. Oxidation immediately occurs in the "air space" in the tank. On the other hand, with a Hydrogen Peroxide system, there is no "air space" in the tank and the H2O2 needs a catalyst in order to oxidize the iron. That catalyst is the media. The iron is oxidized on the media and backwashed out. Additionally, do not forget that Hydrogen Peroxide is a better oxidizer than oxygen and since the oxidation does not occur in the "air chamber" there is virtually no fouling.
Fred Hemer
February 3, 2019 at 3:02 PM
Thanx So with my well! I have a cistern added, low (yield well)! I find I have a lot of already oxidized material in the cistern that material is ending up in my iron filter and softerner head tends to coat everything with brown red slippery material Have quite high manganese , .734 ml/litre a bit of .188 iron ml /litre, ph 7.5 So from the cistern to the iron filter the pipes and the iron filter tends to give issues getting slined up on a fairly regular basis ! Can't seem to find a way around the issue ! Any ideas on what A guy can do in this case???
Doug Barduca
February 16, 2019 at 1:01 AM
Hello, My softener is starting to allow more iron to pass through. Literally just started this last month. The first company we had out last week suggested the Nelson aio system with fleck backwashing system. I was told that with nightly backwashing the injector etc becoming clogged would not be an issue? Obviously, your article seems to state differently. So will this occur regardless? My current setup just has a regular whf I have to swap every 4-6 months due to this sludge already. I do not want to be trying to clean that hunk out. Besides the 200-300 average per year what is the difference in cost between the h2o2 system and the chemical free air version.
Mark Timmons
March 6, 2019 at 8:38 PM
The Peroxide system always works. No sludge!
Isabelle
March 12, 2019 at 11:28 AM
I have a well at my cabin in Sevierville TN. We replaced the whole house water system with a new Culligan system 3 years ago when we purchased the property because of orange tinted water and stains. Culligan promised that there system would take care of the problem. Well, here we are with the same problem that has never been corrected and tons of money being spent on filters. We have a water softner and use both a 25 micron prefiler; 1 micron post filter and a 75 micron pre filter; 25 micron post filter. I need a solution. My cabin is an overnight rental and I need to stop the complaints about the water. Please help me. Will the peroxide system help or do I need to consult a well water company?
Mark Timmons
March 12, 2019 at 10:34 PM
Yes, it most likely will fix it, but before I can say 100%, I would need to see a Laboratory analysis of the water: https://www.uswatersystems.com/us-water-lab-water-test.html
Philip Fiorentino
April 1, 2019 at 9:15 PM
I used aeration for iron removal for 15 years. Looks just like the picture posted (iron sludge), which means it is working! Yes have to clean and maintain every couple of years, and the aerator has to be looked after, but definitely takes the load off the softerer.
Mark Timmons
April 3, 2019 at 8:34 PM
How much iron do you have? That's the million dollar question. I can say that I haven't used a furnace in 15 years, but if I live in Key West, what correlation is that to people who live in Alaska?
John Gilbert
April 24, 2019 at 9:29 AM
Thank you for this article and it's in-depth discussion of the problems inherent to air-injection iron filters as there is so much misinformation on the Internet regarding proper iron filtration. I own a cabin on a mountain in West Virginia that uses a cistern system that feeds to the well. Currently there is no iron filtration in place, only one carbon sediment filter. The water has low pH of 5 ppm, also a hardness, nitrite and nitrate level of 0 ppm. Due to the low pH it will most likely require a soda ash injection before the pressure tank so the iron filtration will work properly. I have spent weeks deep diving the subject and until I read your article I was considering ozone injection systems for iron filtration. Since reading your article I dove a little deeper and found a new twist on the air/ozone filter, specifically designed to eliminate the issues you discussed. I would love to hear your opinion on the system. Thanks again for your article. I am sure it has helped many avoid the problems related to air injection and saved people the money and headaches associated. Since this does involve a product from another company it is fine with me if you choose not to post this but instead just reply to me directly through my email. I would be using the filter add-on products, the ozone generator and peroxide injection. The iron filtration product link is: http://csih2o.com/products/iron-sulfur-filters/sidekick-single-tank-aeration-filter Thanks again for your article and any assistance you can provide..
Mark Timmons
April 24, 2019 at 10:49 AM
John, You are a wise man. We collaborate with CSI on some projects. In fact, we currently are using that technology with our Smartphone app which gives us better control of the system. The advantage of this type of air injection is that since the valve is on the side of the tank, it comes in contact with no air. The air is injected into the bottom of the tank. It can use ozone, but our tests show that is not as effective as using hydrogen peroxide (only for a few seconds each time it regenerates). It will use very little H2O2, but will be very effective. This product will be released by us in the next 20 days. If you want to try one, let me know. I would like to see a good laboratory analysis, like this one: https://www.uswatersystems.com/us-water-systems-professional-lab-water-test.html
John Gilbert
April 24, 2019 at 9:37 AM
Follow up: For some reason important information regarding iron levels did not make the cut, probably due to my use of parentheses. Here is the missing info: The water has low pH of 5 ppm, also a hardness, nitrite and nitrate level of 0 ppm.
John Gilbert
April 24, 2019 at 9:42 AM
Okay, I am confused, the info is still missing. Here it is again: The water has low pH of minus 4 ppm probably due to the cistern and iron levels of plus 5 ppm, also a hardness, nitrite and nitrate level of 0 ppm.
Mark Timmons
April 24, 2019 at 10:50 AM
I want to see a good detailed water test like the one in the link I attached.
Elizabeth Loveday
July 24, 2019 at 6:47 PM
We can’t seem to get our PH level up over 6.8 since we installed an AIO system 10 months ago along with a brand new water conditioning system. Our iron levels are at 7 ppm before treatment. The technician was here this week and changed the valve in the AIO system because our water is again acidic and staining the tub wall. The AIO value was completely clogged with iron. He said that could have been causing the neutralizer not to work properly. We have been going round and round with our water systems company for months now. Should we have the AIO removed? It is only 10 months old. We are not sure if our new water conditioning system can handle the iron. Our old water conditioner did not take all the iron out but it was 22 years old. We have the media replaced but it did not help. What to do. I feel like we are responsible to trouble shoot this instead of our service company. Help! Also, what is the correct order for all these things to be installed? Thanks for any help you can give us.
Mark Timmons
July 27, 2019 at 2:43 PM
Most AIP systems are nightmares, but our new OXi-Gen eliminates all those iron plugging problems: https://www.uswatersystems.com/flexx-oxi-gen-aeration-iron-and-sulfur-filter.html That said, the first step is to get a detailed laboratory water analysis: https://www.uswatersystems.com/us-water-systems-professional-lab-water-test.html
Kenny Kieser
August 18, 2019 at 10:50 PM
I have 18 ppm iron . we run through an air injector and then a chlorine injector to a 800 gallon holding tank from there as you use water it is drained to another 800 gallon tank but when first tank refills and you are drawing on second tank you don't always get settled water due to water coming in first tank mixing with settled water needing a way to to filter water going to second tank because after second tank we have two iron filters and a softener that can do the job of filtering settled water but not the remixing of the water during long draw times
Mark Timmons
August 19, 2019 at 9:15 AM
Kenny, We can solve your problem but I need a lot more information. The way you are trying to do it is destined to fail. Let me know when we can talk...
Brain2000
September 4, 2019 at 12:07 PM
At our second home, we have HUGE amounts of iron and manganese from our well, with a pH of around 6.5. The water was so orange that you couldn't tell if you flushed the toilet or not. We installed a Katalox tank with air injection almost 3 1/2 years ago, and the system has worked flawlessly without any maintenance other than a weekly backwash (yes, weekly, not daily as recommended). I'm not disagreeing that H2O2 is a better oxidizer, but I'm also not so sure that they will just sludge up like that unless something was done incorrectly.
Mark Timmons
September 8, 2019 at 12:13 PM
Your particular water chemistry very much comes into play. We have had good results with Katalox at times, but overall, the experience with it was not good. With a pH below 7.00, you are not going to typically have bacterial iron and organics and the things associated with it. You say you have a HUGE amount of iron. Any amount over 0.3 ppm will stain, so 2.0 ppm is a lot, but some people have 5 ppm, 10 ppm, 20 ppm, 50 ppm... and more. Katalox will not work there. H2O2 works because (done properly) it will not form that sludge since it is injected continuously.
John Lynch
September 12, 2019 at 5:15 PM
Hello: I need to replace a macclean uif 1001 iron removal system. The valve head is broken and parts are not available. The fleck 5600 would work but is made for a threaded tank and mine is a clamp type. Does anyone make an adapter? Thank You.
Mark Timmons
September 15, 2019 at 7:30 PM
If the head is broken, then the media is likely bad and the tank is a horrible design. It's time to replace the entire system.
mike s
October 18, 2019 at 1:48 PM
I am getting excessive air in my final product of water for my home. It is a well system. I have the nelson AIO system before my softener. I tried to talk to the good people at nelson about this and they say its normal to have a little air it should dissipate after 30 sec or so. Mine does not it is like the water is pure seltzer water. Like alka seltzer. What is a cure for all the air?
Mark Timmons
October 20, 2019 at 9:41 PM
That is one of the many reasons we do not use that type of AIO. Switch brands or quit using an AIO.
Travis Reed
January 9, 2020 at 4:55 PM
I just moved into a house that has a AIO iron filter with centaur carbon I believe, that is brand new, less than a month old. The iron is 10ppm and get a sulfur smell from Hot water. Can I use hydrogen injection before the AIO filter and use it’s catalytic carbon to filter what the hydrogen peroxide oxidizes and peroxide out.
Mark Timmons
January 15, 2020 at 8:57 PM
Absolutely, just make sure you do it with a proportional injection system like this: https://www.uswatersystems.com/us-water-proportional-injection-tank-system-3-4.html Use stabilized OXi-PRO 7 H2O2 (because others degrade too fast): https://www.uswatersystems.com/neutra-sul-hydrogen-peroxide-2-2-5-gallon-bottles.html Also, make sure the catalytic carbon tank is large enough. Many are too small. Call one of our Water Experts if you have questions.
Robert G
March 12, 2020 at 9:19 AM
How much H2O2 is used by the system per year.
Mark Timmons
March 15, 2020 at 1:01 PM
Of course, it depends upon your water quality and amount of water used, but our Oxi-Gen systems average about $70.00 a year and the inFusion averages about $250.00 a year.
Kevin Hall
March 17, 2020 at 7:01 PM
i'm hearing that our well water has approximately 6 ppm of iron. Would you recommend this system? If not, which one would you recommend? Thank you -
Mark Timmons
March 20, 2020 at 9:24 AM
Probably, but I would like to know more about your water. pH, Hardness, Manganese and possible competing contaminants.
Iris Trevino
March 21, 2020 at 3:18 PM
Hello. I'm on a well that produces 48mpg . Please see our water results , .501 iron , .261 manganese, 290 hardness, 4.7 turbinity. What type of system do you suggest for us to purchase.
Iris Trevino
March 21, 2020 at 3:19 PM
Hello. I'm on a well that produces 48mpg . Please see our water results , .501 iron , .261 manganese, 290 hardness, 4.7 turbinity. What type of system do you suggest for us to purchase.
Mark Timmons
March 27, 2020 at 1:12 PM
What is mpg? I would also need a lot more information about other competing contaminants. Do you have a detailed water test?