Having rust in your water supply can be unbearable. Aside from changing the color of your water and giving it a bad taste, rust can give your clothes, toilet and sinks very stubborn stains. When rust builds up in home appliances like dishwashers or kettles, it damages them and shortens their lifespans. It can also clog your pipes.
While rust does not pose a severe health risk, it can be unpleasant to cook with reddish-brown water. Rust-contaminated water also gives beverages like coffee a weird aftertaste.
What is Rust, and Where Does it Come From?
Rust is the common name for a chemical compound called iron oxide. Your well water gets contaminated with rust after coming in contact with rusty metallic surfaces or appliances. There are different types of rust (iron oxide), and you can find these four in water.
- Ferric iron (red-water iron): This iron compound turns water reddish. It’s usually present in water sources high in oxygen. It doesn’t dissolve and causes clogging of pipes.
- Ferrous iron (clear-water iron): Ferrous iron dissolves in water, so it’s not visible. It’s found in water sources that don’t have a lot of free oxygen. Water contaminated with ferrous iron may appear clear, but it stains fabrics and ceramics. Ferrous iron also affects the taste of water.
- Organic iron: You can find it in shallow wells or wells mixed with surface water. It causes worse staining than ferric or ferrous iron.
- Iron Bacteria: This is a bacteria that feeds on iron. They usually get introduced into well water during well construction or repairs. These bacteria convert ferrous iron into reddish slime that settles everywhere from toilet tanks to pipes.
When rainwater trickles through the soil, it absorbs iron on its way and gets deposited in an aquifer. Iron is very soluble, so it quickly dissolves into the water and pollutes it. Rust can also come from the water that seeps out of iron-containing rocks. Water is more likely to be contaminated by iron if the pH is low.
How to Find Out if There is Rust in Your Water Supply
Rust contamination is usually easy to detect, even at the lowest levels. Here are some signs that your water contains rust:
- If your water gives off a reddish color, then there’s a high chance that you’re using rust-contaminated water. Even clear-water iron will give off a reddish color if you leave it to sit for a while.
- Red or brown stains on your toilet and kitchen fixtures often indicate iron contamination in your water.
- Metallic taste and odor. Once the iron concentration is higher than 0.3 ppm, you’ll notice a metallic smell or taste which will even be stronger in your tea or coffee.
- If you find slimy clumps in your water, it may be a sign that there are deposits of iron bacteria in your pipelines. The clumps are materials that break away from the iron bacteria.
If you suspect that there’s rust in your water supply, you should run a water test to know the exact kind of iron you have in your water. A water test will help you understand what filtration method best removes the rust.
How to Remove Rust from Your Well Water
There are different filtration techniques for each type of iron. This site – https://www.best-osmosis-systems.com/how-to-remove-iron-from-well-water/ – perfectly explains techniques best suited for each kind of rust contamination.
If your water is contaminated by ferric and ferrous iron, here are some filtration tools you can use.
Whole House Iron Filter
Whole house iron filters are mainly used to filter ferrous iron. They are placed at the main water line so that all water coming into the house is filtered and rust-free. Whole house iron filters can treat water with iron levels up to 15 ppm. They work by turning the ferrous iron to its ferric form using an oxidizer (a chemical that adds oxygen to a substance). This ferric form is insoluble and gets trapped in the filter bed.
Chemical Oxidizer Iron Filter
This filter oxidizes iron using chemical compounds like ozone, chlorine or hydrogen peroxide. Allow the water and oxidizer to stay in the retention tank for a while. Prolonged contact ensures that all the iron in the water is fully oxidized. Afterwards, the system filters out rust and chemical byproducts with a regular water filter.
They are mainly used for ferric iron. Since ferric iron is insoluble, it only requires mechanical filtration. Sediment filters may even handle iron concentrations of up to 10 ppm.
An ion-exchange softener can also remove iron from your water. However, it can only remove ferrous iron of about 3-5 ppm in concentration. It cannot filter ferric iron. Also, if your water is heavily contaminated with iron, you may risk damaging the water softener. If the pH is too high, the water softener may worsen the situation by changing ferrous iron to rust quickly.
Organic iron is even harder to remove than ferric or ferrous iron. This is because the compounds don’t oxidize fast enough. You will have to do chemical oxidation and then some mechanical water treatment to remove organic iron.
Although consuming small quantities of iron is not dangerous to health, you still need to keep your iron levels at a minimum. Ingesting high amounts of iron over a long period can cause serious health complications. It’s best to remove iron from your water entirely for cleaner, healthier and better-tasting water.