What Causes Green Stains from Well Water?

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The green stains from the well water are caused by the corrosion and dissolution of the copper pipes and fittings. Normally, the water quality and improper electric grounding lead to corrosion, causing excessive amounts of dissolved copper to be dispersed in water, causing green stains.

Can Well Water Cause Green Stain?

Definitely! Well water can cause green stains especially when the well water has a low pH, also known as the pH imbalance. A low water pH means that the well water is acidic. Any well water with less than 7 pH level is acidic.

So, whenever the acidic well water flows through the copper pipes, small metal particles dissolve in water. And, once this water remains on a surface that’s isn’t dried off, it eventually stains the right surfaces.

Well water can also cause green stains if it is salty. Salty well water has components of chloride concentrates. These concentrates can be so aggressive to copper or stainless lead pipes, thus causing corrosion.

Sometimes well water can be contaminated with large amounts of soil, silt, sediments, or other particles. These contaminants such as soil always contain bacteria that can cause a certain type of mold stain if dissolved in well water. A good example is the Penicillium mold that is usually green in color and is often found in the bathtubs.

What’s more, the high velocity of well water can create possible stains on your surfaces and fixtures. This is because when water is flowing at high speed it wears downs the inner lining of the pipes through water turbulence. In return, if these small inner lining particles are not wiped from the surface, they may cause stains.

What Causes Green Staining from Well Water?

Green staining from well water can either be caused by corrosive water, mold or mildew, or electrolysis among others.

Corrosive Water

Corrosive water is so destructive especially when it comes in contact with some of the piping materials. For instance, bathroom piping made of copper, lead, or other metals is highly susceptible to corrosion. So, if you are encountering green stains inside your bathroom, it means they could just be the insides of your corroded pipes.

As I mentioned earlier, you can tell that your well water is corrosive if its pH is low, if it has calcium concentrates, or if it is hard. So, the best way to avoid the green stains caused by corrosivity is to have your water tested.

Mold or Mildew

Another cause of green stain from well water is mold or mildew, particularly penicillium. Commonly known as blueish greenish hue, this mold can be found everywhere in the air and soil.

Therefore, if your water contains contaminants such as soil and sediments, it may lead to the greenish stain you see. This is because the mold found in the soil might find itself through the piping, thus leading to the greenish or blueish color in your bathroom.

Electrolysis

Electrolysis occurs particularly when two different kinds of metals come into contact in the presence of water. When water passes through these metals, the one that is more reactive will start to corrode, dispensing metal particles in the water.

For example, a connection between a steel pipe and a copper pipe will cause the copper pipe to corrode because copper metal is more reactive than stainless steel. So, you are likely to see green stains on your appliances from well water if your plumbing is composed of these two types of metals.

Salty Water

Salty well water is another contributor to the green stains you see on your surfaces. Salty water has a high concentration of chloride which lowers the pH level of the well water. And once the water level is lower than 7.0, corrosion of copper pipes can take place easily.

Secondly, if the total dissolved solids (TDS) of your well water is more than 250 mg/L, it is an indication that the water is salty, thus the presence of elevated chloride concentrations can cause excessive corrosion.

How Do You Get Rid of Green Water Stains?

Green water stains can that you see on surfaces such as the bathroom tubs and toilet bowls can be very expensive if not dealt with in the long run if immediate action is not taken.

Here are various ways to get rid of green water stains.

How to get rid of stains caused by acid water

Use White Vinegar.

Take a plain white vinegar then pour it on a piece of clean cloth or a sponge. Using the wet cloth, apply it to the stain then scrub. You can use the same solution if you want to remove green stains from your plumbing fixtures.

Use Ammonia

In case the mild acids don’t remove the stain, use a mixture of soap suds and ammonia. Following manufacturer’s dilution guidelines, mix half water and half ammonia, apply it on the strain, scrub, then rinse. But, remember to flush your drains with water after using ammonia cleaner.

Use Baking Powder

Baking powder can also come along in case you need to get rid of the green water stains. It is often used as a mild abrasive in case of stubborn stains. Apply its mixture with water on a non-abrasive sponge and scrub the stain.

Use Phosphoric Acid

If you encounter stubborn green stains, use phosphoric acid or oxalic acid. Mix 1 part of phosphoric acid with 10 parts of water, then scrub it on the stain. Rinse the part with water then flush your drains with clean water.

How to get rid of green water stains caused by corroding pipes

Just like getting rid of stains caused by acidic water, you will use homemade acid cleaner to remove green water stains caused by corroding pipes. This time you will have to mix vinegar and baking powder into a paste. Apply the mixture to the stains, then wait for about 10 minutes before wiping off.

To get rid of green water stains caused by mold or mildew

Even though your bathroom might be prone to mold growth because of the amount of moisture readily available, you can still get rid of the mold. And the best way to do this is to control the moisture and leaks.

You can opt for either of the following ways;

Make sure you squeeze the water off the shower after showering.
If you have a fan or air conditioner, run either immediately after showering.
Trap moisture in dark, tight spaces by sealing any grout lines using tile.

Use Lemon Juice and Tartar

Another easy method to get rid of water stains is to use lemon juice and cream of tartar to create a mildly acidic paste that may remove copper stains with some light scrubbing.

Use Calcite Chips

You can also reduce corrosivity at a low cost by adding calcite (calcium carbonate) chips to the bottom of your well. Even though sometimes it might alter water quality, it is one of the best and cheap ways of avoiding green stains.

Reverse Osmosis

Finally, you can opt for reverse osmosis (Ro) system in case you want to deal with elevated chloride concentrations. This system will remove every sediment and chlorine in water with a prefilter to polish the well water before it enters a dedicated faucet.