Do Water Softeners Remove Iron? (You Might Be Surprised)

If you have iron and hardness minerals in your drinking water, you’re probably wondering whether you can effectively tackle the problem with a water softener.

In this guide, we’ve answered the common question: do water softeners remove iron?

🤔 Can A Water Softener Remove Iron?

Yes, a water softener can remove iron from well water.

However, a water softener isn’t built to tackle heavy iron contamination, and it has other limitations, too – including the type of iron it can remove and its ability to flush the iron from the resin bed during regenerations.

How Can I Make My Water Softener More Effective At Removing Iron?

If your water contains low levels of iron, the general recommendation is that you increase your softener’s water hardness setting by 4 for every 1 PPM of iron detected in your water.

So, if you have 1 PPM of iron, simply increase your hardness setting by 4.

If you have 3 PPM of iron, increase your hardness setting by 12.

That means more salt will be used to account for the iron content in your water, and the softener’s regeneration frequency will be slightly increased.

You should have inputted this information when you first set up your water softener and tested your water hardness. It’s easy to go back and amend the setting when you learn of your water’s iron content.

🧐 What Type Of Iron Can A Water Softener Remove?

A water softener can only remove soluble ferrous iron (or clear water iron) from well water.

Ferric iron, on the other hand, is insoluble and gives water an orange tinge. It may also show up in your water as flecks of rust.

Ferric iron may clog and damage your water softener resin, so it’s important to use some form of pre-treatment, like a sediment filter, to prevent the iron from entering the resin tank.

Most water softener systems come with a sediment pre-filter. So, as long as your ferrous and ferric iron levels are low, you can use a softener and sediment filter combo to remove iron from well water.

Does A Water Softener Remove Iron Bacteria?

No, a water softener doesn’t remove iron bacteria.

Iron bacteria (which creates slimy gunk in your toilet tank and other plumbing fixtures) is particularly challenging to remove, and most iron filters can’t tackle this contaminant.

The best ongoing water treatment solution for bacterial iron contamination is a chlorine injection system.

But if your iron bacteria levels are particularly high, you might need to employ a stronger water treatment method, like shock chlorination of your well.

Related: Will a water softener remove sulfur smell?

🔎 How Much Iron Can A Water Softener Remove?

A water softener can remove up to 3 PPM (parts per million) of iron.

So, if you have 0-3 PPM of iron in your well water, a water softener should handle this nicely.

But if you have more than 3 PPM of iron in your water, we don’t recommend using a water softener to remove iron.

More than 3 PPM of soluble iron may damage the resin beads in the softening tank.

To understand why, let’s quickly look at the ion exchange process.

Ion exchange takes place in all conventional salt-based water softening systems.

Salt from the brine tank is used to regenerate the resin. This sodium is charged, like the hardness minerals in the water that travel through the resin tank.

The hardness minerals are attracted to the resin, which has an opposite charge, and stick to the resin. The iron particles in water do the same.

In exchange, sodium ions are released into the water, which balances out its charge.

Eventually, the resin becomes saturated with hardness and iron minerals, and depleted of sodium ions. In order for the ion exchange process to continue working effectively, the softener has to perform a regeneration cycle, which flushes the resin beads and replenishes the sodium.

Regeneration removes the hardness minerals, but doesn’t remove accumulated iron as effectively. This means that, over time, the resin will experience iron fouling – a buildup of iron that clogs up the resin beads and reduces their capacity for softening.

If your water has low ferrous iron levels, this issue can be managed by using a resin cleaner every 6-12 months, which should clear out most of the accumulated iron.

However, excessively iron contaminated water may foul the resin beyond repair, shortening its lifespan and preventing it from properly softening your water.

🆚 Conventional Softeners vs Dedicated Water Softeners For Iron

You might have seen a few dedicated well water softeners that are designed specifically for treating hard water with iron. How do these compare to conventional water softeners?

The truth is that they’re no different when it comes to iron removal. Like conventional salt-based softeners, these well water softeners only remove up to 3 PPM of iron.

The only difference is that some manufacturers use a stronger resin that’s more resistant to iron fouling, so iron shouldn’t degrade the resin in the way that it would in a basic water softener.

You might come across an iron filter and softener combo, which is a bit different: it combines the manufacturer’s salt-based water softener with a whole home iron filter, providing effective softening and iron removal in a single solution.

We’ve discussed iron filters in more detail below.

🆚 Water Softener vs Iron Filter: Which Is Best For Iron Removal?

There’s a better solution for removing iron: a dedicated iron removal water filter.

There are numerous different filter types available for removing iron, including:

• Sediment filters (best for ferric iron or rust)
• Some KDF filters (can reduce both types of iron)
• Injection/oxidation systems (convert ferrous iron into ferric iron, then remove it from water)

The most popular iron removal solution is the injection/oxidation system, which comes in a few different configurations:

• It might use an oxygen bubble to oxygenate the water, or it might use a chemical (such as chlorine, ozone, or hydrogen peroxide)
• It might use one of several media or resins (including birm and manganese greensand)

How does an injection/oxidation system compare to a water softener for iron removal?

The biggest difference is its iron removal capabilities. An oxidation iron filter can reduce iron concentrations to 10, 15, or even 20 PPM, depending on the effectiveness of the oxidation and filtration combination.

So, if you have very high concentrations of dissolved iron in your water, it makes sense to use an iron filtration system instead of a water softener.

If you want to address hard water and iron, and your water has particularly high iron levels, the most effective solution is to combine a water softener system with an injection/oxidation filter, which will protect the softening resin from iron fouling and remove as much iron as is present.

📑 Does A Water Softener Remove Iron? Final Word

So, water softeners do remove iron, but don’t rely on a water softening system to remove high levels of iron from well water.

In fact, if your well water supply does contain large concentrations of iron, using a water softener alone to treat your water may result in early degradation of the resin bed, compromising its softening performance.

We strongly recommend testing your water if you suspect that there is iron present. If more than 3 PPM of either ferric or ferrous iron is detected, look into water treatment equipment for removing iron before you spend your money on a water softener.