Iron and Manganese Water Filters
Why You Need an Iron Filter: Iron causes black, grey or orangish-red stains on fixtures, clothes and showerwalls. Buildup inside pipes and toilet tanks. Metallic taste and/or smell. Sulfur causes a rancid rotten-egg odor which is usually readily apparent.
Causes: Rock and gravel formations contain large amounts of these elements. Sulfur is one of the most abundant metals in the earth's crust and usually occurs in conjunction with iron.
Health Concerns: Iron and sulfur are generally a nusiance and something that homeowners will not tolerate. Some harmful bacteria require iron to grow, and therefore, it can make removal of these organisms more difficult. Ingesting sulfur is not a health concern, but can be quite unappealing.
What does an Iron and Manganese Water Filter do?
If you have iron, which is sometimes called rust, in your water, you undoubtedly know it! You know it because of all the orange, red or black stains on your plumbing fixtures, shower walls, toilet tanks, your clothing and in fact, anything water touches. Before we go any further, you should know that US Water Systems, has over 43 years of experience in using iron and manganese water filters successfully all over the country. You have come to the right place if you want to solve your problem once and for all!
It is common for water which contains iron to also have levels of manganese, hydrogen sulfide and/or arsenic. In some cases, sulfur, manganese and arsenic can even be removed in exactly the same manner that you remove iron.
There are many types of iron, but for our purposes we generally divided them into two main categories: (1) soluble or ferrous iron; and (2) insoluble or ferric iron. There is also bacterial iron, as there sulfate reducing bacteria as well as elemental sulfur.
Soluble iron, or “clear water” iron oxidizes to insoluble or red iron in the presence of oxygen either in the well or in your home. This type of iron is identified after you’ve poured a glass of cold clear water. If allowed to stand in the presence of air, reddish brown particles will appear in the glass and eventually settle to the bottom. When insoluble iron, or red water iron is poured into a glass, it appears rusty or has a red or yellow color. Insoluble iron can create serious taste and appearance problems for the water user.
When iron exists along with certain kinds of bacteria, problems can become even worse. The bacteria consume iron to survive and leave a reddish brown or yellow slime that can clog plumbing and cause an offensive odor. You may notice this slime or sludge in your toilet tank when you remove the lid.
Testing for Iron in Your Water
When treating for iron or manganese in your water, it is imperative that you obtain a good water analysis. This is not just for iron and manganese, but for a number of other contaminants, including hardness, pH, nitrate, tannin, sulfur, TDS and others. The inter-relationships of the different competing contaminants will help in choosing the best technology to solve your specific iron, manganese, sulfur and/or arsenic problem.
With a good water analysis, US Water will be able to confidently recommend the appropriate treatment and will provide a Performance Guarantee with the system. There are numerous methods by which iron, sulfur, arsenic and manganese can be removed from the water, and most operate on the principal of oxidizing the iron (oxidation) to convert it from a ferrous (dissolved or soluble) to a ferric or undissolved state. Once it is converted to the ferric state, iron can be filtered.
In instances where the iron is high and the pH is low (below 5.8), a Synergy Water Softener can effectively remove extremely high levels. We have removed upwards of 50 mg/l with just the Synergy softener. However, when the pH is higher, that is not an option. In most cases, iron and manganese need to be oxidized to be removed. Sulfur must always be oxidized to be removed – a water softener can’t touch it!
Backwashing Iron & Sulfur Filters
A backwashing filter, often called an iron filter or oxidizing filter, is the most widely used system for removing iron and sulfur. Iron filters work by oxidizing the iron and/or sulfur and then filtering it out through the media bed. The best medias at removing these contaminants are medias that are manganese dioxide based or coated media. Birm is coated with less than 0.5% of manganese dioxide which is why it is limited in application. Greensand Plus is a little higher in manganese dioxide and Filox, Pyrolox and MangOx are 60 to 80% manganese dioxide.
However, the most common reasons for filter failure are a lack of flow in backwash or a lack of frequency of regenerations. Most manganese dioxide-based medias are extremely heavy (up to 120 pounds a cubic foot), making them extremely difficult to backwash. Filtration using oxidation is the most common method of iron removal, but many medias can be problematic. They will work well for a few months and then load-up with the iron or manganese they are trying to remove. Oxidizing filters use an oxidizer such as ozone, oxygen, chlorine or hydrogen peroxide to boost the oxidizing properties of the water being treated and allow for better iron removal.
Iron filters and sulfur filters have been used for years with varying levels of success or maybe we should say “unsuccess.” As mentioned earlier, the biggest problem with most iron filters is the weight of the media, because the heavier the media, the more water and pressure it takes to backwash.
Medias like Filox, Pyrolox and MangOx weigh from 114 to 125 pounds per cubic foot. For example, to backwash a 1.5 cubic foot tank (10” x 54”) of Pyrolox or Filox or any typical manganese dioxide-based media, would require 15 Gallons Per Min (GPM). Backwash and rinse time can be up to 20 minutes. Do the math! Yikes! That’s wasting a lot of water. Some systems waste up to 300 gallons of water per regeneration and most need to backwash daily or at least every other day. We think that is wasteful!
Old-style iron filters and sulfur filters are rapidly becoming obsolete due to their inherent inefficiency and massive wasting of water, to say nothing of the fact that many don’t work very well. Additionally, many use either potassium permanganate or chlorine to regenerate as an oxidizer. Potassium permanganate dissolves into water and gives it an intense pink or purple color, and will forever stain things it comes into with if the concentration is too high.
Potassium permanganate is generally held in a tank with a small amount of water at the bottom. The problem is these tanks frequently overflow, and it’s easy to spot the homes where this has occurred by the brown and purple stains all over which cannot be removed – EVER! Additionally, potassium permanganate is a toxic chemical and can cause serious eye injury, is a skin and inhalation irritant, and can be fatal if swallowed. For that reason, most people do not want it in their water. Over the past several years, potassium permanganate has fallen out of favor with savvy water professionals.
Chlorine is also used as an oxidizer by many companies because it is easier to handle and doesn’t leave stains like potassium permanganate. However, chlorine is more insidious than it is dangerous in that during oxidation, disinfection by-products (DBP’s) are created. Trihalomethane (THM’s) are one of these DBP’s and are known carcinogens (cancer-causing agents). If you use chlorine, then you will need to add a backwashing carbon filter after the iron or sulfur removal system to remove the chlorine and disinfection by-products.
Old-style iron filters that use oxidizers such as chlorine and potassium permanganate are becoming obsolete as new and better technology have emerged. Ozone is an excellent oxidizer, but the inherent high cost of generating ozone and equipment needed makes the cost prohibitive for most residential applications. We hear many people say “I had an ozone system and it didn’t work very well.” What they say is probably true, because it was likely undersized or misapplied. An ozone system for a typical 3 bathroom home would consist of the following components:
- Oxygen Concentrator/Air Dryer – Prepares the oxygen so that ozone can be created
- Corona Discharge Ozone Generator – Needs to be adequately sized so that more ozone is made than is actually needed so that the oxidation is complete
- Injector Manifold Assembly – Insures that the ozone is properly injected
- Vacuum Break – Prevents water from backing up into the ozone generator
- Contact Tank – This is where the raw water comes into contact with ozone-enriched water
- Circulation Pump – Continuously circulates ozone so that the contact tank is always saturated with ozone
- Ozone Destruct Device – Ensure that any excess ozone is destroyed before entering you house lines
- Catalytic Carbon Backwashing Filter – Completes the oxidation process and destroys the ozone completely
The picture to the left is a skid-mounted ozone system, which includes all of the components listed above. Such a system can cost $8,000 to $12,000, but it will do a great job for many years with virtually no maintenance. In the case of ozone, it’s go big… or go home. If you are not willing to spend the money, ozone should not be a consideration. There are now companies who are introducing a tiny amount of ozone into a backwashing filter tank and claiming that it does all kind of fabulous things. If you believe that, we may have a bridge that we could sell you… To oxidize properly in water, the mass transfer of ozone into the water cannot be underestimated.
Chemical-Free Oxygen Systems
Over 20 years ago, we begin experimenting with introducing air (which is 21% oxygen) into a backwashing tank of manganese dioxide based media. We did this with a water softener valve which was modified to suck air instead of salt brine. While we do not claim to be the first to do this, there weren’t many other companies that we were aware of who were doing this. Others have used air pumps, air injectors and micronizers, all of which added 21% oxygen to the system.
Oxygen is an excellent oxidizer of iron, sulfur and manganese and recently, US Water introduced the “next generation” in its line of oxygen systems called the inFusion Purely O₂ Chemical-Free Iron and Sulfur Eradication System. It is built on out commercial water softener platform with a 1” high flow (up to 35 GPM) control valve that draws in oxygen from the air to oxidize the iron and sulfur. It does not use the typical manganese dioxide media, but rather uses the lighter and much more effective “Catalytic Carbon” which acts as a catalyst between the oxygen and the iron and sulfur. As mentioned earlier, atmospheric oxygen is of a 21% concentration, but the new inFusion Purely O₂ system takes it a step further (well maybe 4 or 5 steps further) by offering the option of an oxygen concentrator which concentrates the oxygen up to 93%, which is about 450 percent better than 21% oxygen. So, if you have really bad iron or sulfur, this chemical free method will handle about any level of sulfur or iron thrown at it. No chemicals, no high cost of operation and no ozone – just clean, fresh water!
Then We Have Katalox Light...
To begin with, Katalox is a revolutionary new media developed in Germany. Katalox Light is engineered with a unique manganese dioxide coating technique on ZERSORB (which is a very lightweight media). It has a manganese dioxide coating of 10%, which makes it much lighter and easier to backwash than other manganese dioxide-based medias such as Filox and Pyrolox… or just about any media ending in “lox.” Katalox Light is ANSI/NSF 61 Certified for drinking water applications and has met the ANSI/NSF 372 lead-free compliance.
The Katalox Light media has a very high surface area which filters down to three (3) microns and immediately stops oxidized or precipitated forms of Iron and Manganese from passing into the water stream. It generally needs backwashed every 2 to 3 days, unlike other heavier media that requires daily backwashing.
In short, Katalox Light is a revolutionary media that is changing the way iron and manganese are removed from water. We are so confident in its ability to remove iron and manganese that we offer a one-year money-back guarantee. However, we do not recommend it when iron or sulfur-reducing bacteria is present. Katalox Light works very well when applied properly. To find out if it is the right solution for you, call one of Certified Water Specialists at 800-608-USWA or e-mail us at [email protected] for details.
If you want to go salt-free, we also have our Green Wave Salt-Free Water Conditioners coupled with our inFusion, Katalox or Oxi-Gen systems.