How do you remove rust (iron) from your water?
A WATER SOFTENER CAN REDUCE IRON TO BELOW THE THRESHOLD OF STAINING, BUT IT CAN NOT TOTALLY REMOVE IT!
Under some circumstances, a water softener will work for a while, but the resin bed will gradually become fouled with iron over months or years, decreasing its efficiency at removing the iron.
To totally remove iron, one must utilize the following: (1) Oxidation and filtration; or (2) Sequestration using polyphosphates.
POLYPHOSPHATES - We will discuss sequestration of iron with polyphosphates first. Sequestration of iron with polyphosphates does not remove it from the water supply, but keeps the iron in solution, so that it does not produce stains. This is often used when individuals or businesses want to keep the iron from staining in irrigation systems. It is accomplished by injecting a small amount of polyphosphate into the water, typically with a chemical injection pump and a solution tank containing a supply of polyphosphate.
However, it is not perfect in removing iron, as evaporation of the water can still leave an iron residue and the iron often precipitates when the water is heated. Results may very dramatically with sequestration, depending upon a variety of factors, not the least of which is water chemistry.
OXIDATION - Almost any concentration of iron can be oxidized by feeding an oxidizer such as chlorine, ozone, pottasium permanganate, hydrogen peroxide or even oxygen into the water supply. The oxidizer reduces the iron to a small particle (precipitate), which is then mechanically filtered from the water, typically by a backwashing filter with a dense media containing carbon or materials.
In my thirty-plus years of experience, I have personally tried every method known to man to remove iron. Today, I primarily use hydrogen peroxide, as it is a much better oxidizer of iron than either chlorine or potassium permanganate and does not leave excess air in the water like oxygen systems. Unlike chlorine, hydrogen peroxide is simply hydrogen and oxygen and produces no harmful chlorination byproducts.
A hydrogen peroxide system consists of a chemical injection pump, solution tank, in-line static mixer, and a backwashing filter to remove the oxidized iron. I prefer the hydrogen peroxide system because it completely removes iron and sulfur with totally predictable results. It is my opinion that other methods are not as predictable or reliable in function. A hydrogen peroxide system will remove 100% of the iron. PERIOD!
For homebuilders that build large custom homes with irrigation systems on iron-bearing waters, the hydrogen peroxide system will totally eliminate any staining in irrigation systems, and throughout the home, for that matter. Additionally, a water softener will not have to work nearly as hard once the iron is completely removed. This is not to say that other methods can't work. I am just stating my opinion based upon my extensive experience in treating problem water.
99 Comments
Mark, Thank you for the wonderful article. I am looking in to some possible solutions for getting the iron out of our water. I currently have a Softener and use Rustbuster Salt which does help, but nonetheless, we have a lot of iron in our system and thus in our fixtures. I went to the website you referenced – US Water Systems and looked at a H2O2 system (approx $1000). My question is, generally, how much does this system cost to run? Ie: I currently have to put in about $40 of salt in my softener every 2-3 months; how much H2O2 does this system take? I am really open to getting something if it will take care of the rust problem we have, but at the same time, I don’t want to pay that much money and then discover that it takes another $600/year to run/upkeep the system. Are there resources for purchasing H2O2 that are more economic vs the US Water Systems site? Thanks in advance for any info you can help with. John
Our average customer spends $350/yr on H2O2, but if you buy the peroxide direct from a chemical company you can save a great deal of money. You typically buy 35% and cut it 4 to 1 with RO or distilled water. Be careful and follow all safety precautions with the 35%.
Mark, What about filtration without oxidation for removing lower levels of iron? What are the pros and cons of simple filtration? Thanks.
I just put in a well system for irrigation only, the PH is 6.7 and the Iron is a 15.8 MG/L. Will your Hydrogen Peroxide system that consists of a chemical injector pump, solution tank, in-line static mixer, and a backwashing filter work with this amount of iron? Would I need to add soda ash to increase the PH for it to work properly? Would one backwashing filter work to remove all the iron or would I need two. Jeff
Greg asked: What about filtration without oxidation for removing lower levels of iron? What are the pros and cons of simple filtration? Greg, In order to remove even some of the iron, it would require a filter with a .35 or lower micron rating and you would probably have to change it every day. It’s just not practical or cost effective. Additionally, it would not remove all the iron.
Jeff asked: I just put in a well system for irrigation only, the PH is 6.7 and the Iron is a 15.8 MG/L. Will your Hydrogen Peroxide system that consists of a chemical injector pump, solution tank, in-line static mixer, and a backwashing filter work with this amount of iron? Would I need to add soda ash to increase the PH for it to work properly? Would one backwashing filter work to remove all the iron or would I need two. Jeff, You should not have to adjust the pH and I would recommend using two backwashing filters. The water flows through the first filter and then into the second. This gives longer contact time for filtration, ensures that you are using filtered water (even during backwashing of one tank) and results in overall better performance. When it comes times to change the Centaur media (usually around 5 years), you simply change the media in the first tank and switch the second tank to the number one tank position, putting the re-bedded tank in the number two position.
What aout the Pyrolox system? does it work for iron removal? will the iron preipitate in the hot water heater?
Water Doctor, where have you been all my life? We live in rural SW Minnesota and have terrible well water. We have a Culligan softner but still struggled with our blond hair turning orange along with our appliances. When Culligan would test our water they said it was fine. IT WAS NOT FINE. A local farmer introduced us to peroxide that we inject into our water lines before it enters our softner. It made a world of difference, however, our Culligan man says we are ruining his softner and RO drinking system by doing this. He claims peroxide is only meant for hog buildings. We don’t know if we should continue with the peroxide, drill a new well, or ditch Culligan? Any suggestions? thank you.
Do you have a backwashing filter before the water softener? For the H2O2 system to work properly, you must have a catalytic carbon backwashing filter. You can find them here: https://www.uswatersystems.com/fusion-backwashing-catalytic-carbon-superfilter.html I guess we have a lot of humans masquerading as “hogs.”
Dear Water Doctor: Thank you for posting your expertise for those of us trying to manage our iron heavy water. Our water is corroding our plumbing fixtures and we would like to avoid constant replacement. Our plumber suggests we call a well specialist, but I wanted to contact you to educate ourselves before the bill comes! I have inferred from all the previous emails that we will need to use peroxide in conjunction with a water softener (for which we do not own). Truly, the only issue we have with the water is the corrosion of the well pump (5 years) and corrosion of a pressure tank (also 5 years). I am concerned about using a water softener as I do not want to overburden my septic. It’s a fine balance! I guess I am looking for guidance on where to start, I would like to go in the right direction and fix the problem once! Thanks.
What do you mean by corrossion? I suspect you are talking about something other than low pH. You would NOT use hydrogen peroxide with a water softener. You would use it with a backwashing filter and then could use a water softener to soften if necessary. I would need more information, but with a softener you would use less detergent, chlorine, chemicals and the like which is also very bad on your septic tank.
I have a irrigation system that is supplied by well water. I have iron at 15.8 ppm with a Ph of 6.7. Do you have any recommendations on how to best remove the iron. The water is only used for irrigation. The pump is a 3/4hp and is down approximately 48’. It can produces anywhere from 3 – 16 gpm. All my zones are set up for 10 gpm which is the recommended gpm from the pump manufacturer. At 10 gpm, I have a psi out of the ground of between 72 – 80. Any info would be help full. Thanks Jeff Stratton
What type of backwashing filter do you recommend?
Jeff, How many gallons does it use a day? In what part of the country are you located? Typically, I recommend ththe OxiGen system located here: https://www.uswatersystems.com/residential/ironsulfurremoval.html A pellet chlorinator is also an option. You can call me at 800-608-USWATER to discuss options.
i have learned alot from reading above. i have a iron rich well here in the hill country of texas and other than using iron out and regular pellets, i’ve done nothing to help my softener except a carbon pre-filter. my real question is two part; i have a whirlpool r.o. and i’d like to know if H2O2 will ruin the membrane and also, do you have any idea of the amount of H20 that is dripping down into my p-trap daily? if these questions can be answered, i do appreciate it. Thanks matt