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The Stain Guide: What You Can Do About Stained Clothes

The Stain Guide: What You Can Do About Stained Clothes


When you wash your clothes, you expect them to come out cleaner than they went into the washer. However, water quality issues can lead to the exact opposite–leaving marks and stains for various reasons.

This guide can help you identify some of the most common causes for stains on your clothes. So, take a look and you can have clean clothes once again!

Common Types of Water Stains

Hard Water Stains:

85% of U.S. water has some degree of hardness.[1]  It is not a health concern, but it can be a bother.[2] Hard water can cause mineral buildup in plumbing, lead to poor performance of soaps and detergents, and–you guessed it–stains on your clothes after washing. Hallmark laundry problems that are often attributed to hard water include:

  • Graying or yellowing

  • General soil buildup

  • Stiff feel to fabrics

  • White or gray streaks on colored fabrics

But, what exactly is hard water?

Simply put, hard water is water with high levels of dissolved calcium and magnesium. You may actually be able to actually feel it when you wash your hands with soap. If you feel a thin film of residue left behind, it is likely that you have hard water. This is because soap reacts with calcium to form “soap scum.” Along with residue, it can also leave dingy stains all over your favorite clothes.

Laundry detergents (especially powdered ones) can also attach to the calcium and magnesium in the water. This means that you might have to use more detergent and higher water temperature to get satisfactory cleaning results. However, there are other ways to combat hard water issues in your laundry. 

Some solutions include:

  • Choose liquid detergents rather than powdered ones

  • Add ½ cup of laundry borax to each load

  • Install a water softener system

  • Soak your clothes in 1 cup of white distilled vinegar mixed with 1 gallon of water for 30 minutes. Rinse, then launder.

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Rust-related Stains:

Rusty water is water that contains high levels of iron, which can also impact your laundry. These stains–particularly yellowing–may be exacerbated when chlorine bleach is used. Typical stains include:

  • Yellow, red, or brown spots on your clothing

  • White clothing turned dingy

So, what’s the source of your rusty water?

While sometimes rusty water is caused by corroding iron water systems pipes, oftentimes it is due to iron in your well if you’re on well water.

The best ways to remove rust stains that have already stained your fabrics are:

  • Use a commercial rust remover in your laundry cycle. The acid in these products combines with the iron and loosen it from the fabric, and then holds it in suspension in the water.

  • Make sure to add an extra rinse cycle to ensure that you remove any remaining acid–as it can break down fabric.

Along with solution above, make sure you:

  • Avoid using chlorine bleach. Chlorine will set stains permanently.

  • Don’t put your rust-stained clothes in the dryer. High heat will set stains and make it extremely difficult to remove.

Mold-related Stains:

Ever have pink stains on your clothing–not due to a stray red sock lurking in your white laundry? Serratia marcescens, commonly called "pink mold," is a bacteria that thrives in dark, warm, and damp conditions. So, naturally, it loves growing inside washing machines.

As the name suggests, this kind of mold can cause discoloration–particularly pink blotches. If allowed to spread, it can also cause some very serious health problems.[3] If you notice these types of stains, it’s best to do the following in a well-ventilated area:

  • Dip a sponge in a diluted solution of 2 tablespoons of color-safe bleach and 1 quart of water

  • Gently blot the stain

  • Let the fabric rest for 10 minutes

  • Launder

Prevention is also important. You can prevent growth of pink mold by controlling the heat and humidity levels in your home––a dehumidifier often helps. Also, leave your laundry machine door open after a wash to let it properly dry out.

Copper-related Stains:

Copper seldom occurs naturally in the water supply, but it still may leave stains on your laundry. The corrosion of copper plumbing is generally to blame. While necessary to our health in small amounts, concentrations of 1-5 parts per million (PPM or mg/L) may result in some unwanted effects.[4] Besides an objectionable taste, it may cause blue or green stains on clothes due to oxidation.[5] Moisture and temperature can both cause the copper to oxidize more quickly. The longer the stains are present on your clothing, the more they settle into the material–leaving them more noticeable. While you can use vinegar or chemical cleaners to lessen the stain, these types of marks are the most challenging to remove out of fabric.

Other water related questions? The Tap Score team of water quality experts, scientists, and engineers are standing by to help. Send us a message any time via live chat or email us at

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