Why Is My Toilet Water Yellow: Research Engineer Explains

Every toilet is supposed to be sanitary and clean. In our homes, a toilet should be the cleanest item in a bathroom.

However, it’s not always things go as planned. You could be doing everything to maintain good hygiene in your toilet, but you see yellow water!

Why Is My Toilet Water Yellow? Your toilet water is yellow because of rust. When rust is absorbed into the water, it settles at the bottom of your toilet tank. It coats all the parts of your toilet tank, so some sediments are transferred into the toilet bowl when the toilet is flushed.

The other reason is mineral water. The water could be alkaline or acidic, containing different chemical sediment levels.

Mineral water mixes with chemicals inside your toilet tank. That causes rust due to the iron content in the water. The rust discolors the water making it turn yellow in color.

According to Harry Y Carson, a research engineer, American Cast Pipe Co., pipes made in a rolling mill are not corrosion resistant.

Therefore, they are prone to rust. The factors that make rust resistance of metal pipes have been given very minimum consideration.

When the toilet water appears yellow, you might think someone did not flush the toilet properly. It would be best if you always had in mind that the chances are that something is wrong with your bathroom.

Causes Of Yellow Water in the Toilet

Numerous factors could cause discoloration. They include.

1. Minerals In Water

Water is not always as pure as we may think. It consists of minerals like chloride, and magnesium. If these minerals are minimum, there could be nothing wrong with the water.

If the minerals build up on the walls of the pipes after using them for a long time, they have washed away once the toilet is flushed.

2. Iron

There are those households that use iron pipes for their toilets. The pipes are prone to rust, and when it dissolves in water, a yellow color appears.

According to the United States Geological Survey, iron is a commonly occurring constituent. It may add a rusty, reddish-brown, or even yellow color to water.

The plumbing system used in earlier years contained pipes that easily rusted. If it is the same one being used in your apartment, it needs to be repaired.

The yellow water comes from the rusted fitting contaminated with iron particles.

3. Rusted Bolts

If you notice the yellow water in your toilet bowl, chances are you might find rusted bolts if you look around. These rusted bolts behave the same way as the rusted pipes.

They are made up of iron, which is a long-lasting material, but if it is in contact with water, it reacts, forming rust. That rust produces iron which discolors the water.

4. Stagnant Water in Toilet that Contains Urine

If water is left for days in a toilet that contains urine, mold will feed off of the nutrients that are in urine causing a yellow ring to form in the toilet bowl.

Nutrients in Urine are a food source for Mold

  • nitrogen
  • potassium
  • phosphorus

Why Does My Toilet Bowl Water Look Yellow After Having Turned Off the Water Supply for a Day

Having turned off your water supply, your toilet water could turn yellow. That does not happen to toilets in all homes.

If it does, it means that there is a sign of high iron levels in the water. When the iron is exposed to oxygen, it results in rust.

When the iron particles oxidize, they turn into a distinct red-brown color. That is usually very dangerous for human interaction and consumption.

The sediments in the toilet bowl could also be stirred up by water running through the pipes.

How To Fix Yellow Toilet Water?

Here is a video showing how to remove yellow-colored stains from a toilet bowl:

No one likes the sight of discolored water in the toilet. Imagine having guests and wondering what to do with your toilet.

There is a solution to everything! With toilet discoloration, here are a few tips to solve the problem.

1. Clean The Deposit

The deposit could be in the toilet tank or at the sides of the toilet bowl. The sediment can cause serious issues. Therefore, you need to learn to unclog the toilet before cleaning the deposit.

Use a toilet brush to clean the toilet bowl and a toilet liquid cleaner. Once you are done, flush it twice to see if the problem is solved.

2. Clean The Rust

Rust can be inside the toilet water tank. It is prevalent since it can come from rusted water pipes or bolts.

If rust appears, it happens on all pipes and bolts and once. That is because they are usually regularly exposed to a similar amount of water.

The solution to this problem is scrubbing away rust piled up on bolts at the toilets tank. The other solution is replacing the rusted bolts and pipes.

To scrub the rust away, use a stiff brush that can quickly get rid of the deposits in the tank or bowl of the toilet.

3. Renew The Fitting

Getting rid of the rusty bolts is very easy. You can access them without any issue. However, if the pipe fittings have a problem, you are in for a challenging task.

It is not easy to clean pipe fittings. The only reasonable solution is to replace them. Rusted pipe fittings color the toilet water yellow within a brief period.

Before replacing them, first identify the exact location of the rust. If you trace the rusted fitting, it will be easier to replace it.

It is advisable to consult a plumber if you find rust in the pipe fitting. That is because it is not easy to do it yourself.

Why Does a Toilet Stain Yellow?

If you are wondering why your toilet stains yellow, here are some of the reasons.

1. Calcium Buildup

Under normal circumstances, yellow stains in a toilet are limescale formations caused by hard water. Hard water contains an accumulation of minerals.

The minerals then become visible inside the toilet bowl. The minerals can accumulate in your water pipes, making your toilet clog.

Cleaning the calcium buildups is problematic because it forms a complex structure. You can save your toilet bowl by cleaning any small buildup to avoid future trouble.

2. Rust Stains

Rust also causes a yellow color on the toilet bowl. Rust results from pipe corrosion or worn-out bolts in the toilet tank.

When metal is exposed to water for a long time, it gets corrupted, forming rust. Rust can be yellow in color or brownish.

The only solution to clearing yellow water formed by rust residue is replacing the bolts and the water pipes. The other short-term solution is scrubbing off the rust in the corroded parts.

3. Iron Stains

Water contains iron sediments that are not harmful in tiny amounts. When iron sediments are in massive quantities, the water turns yellow.

The iron sediments oxidize when exposed to the air or oxygen. They then form a brown residue that either settles on the toilet bowl or tank floor. It can also settle on the walls of the toilet tank.

4. Urine Feeds Mold Causing Stains

Urine that is splashed onto the rim of the toilet leaves a deposit overtime if the toilet is not cleaned often enough. Uric acid and proteins will harden and become difficult to remove even with an acid treatment. The proteins are left behind by the metabolism of bacteria and mold that is present on the rim according to a study conducted by Tohru Ohki for the Journal of Surfactants and Detergents.

5. Water Softener Creates Yellow Water

When a water softener starts to break down mineral residue, the water will become discolored, and it will turn yellow. It might seem counterproductive since some of us are using a water softener to get rid of the yellow water in our toilet due to the staining that is in the toilet. Nevertheless, over time this residue that is released into the water will mix with fresher water getting rid of the yellowish color.

How To Remove Yellow Stains from the Toilet Bowl

The toilet bowl can turn yellow due to assorted reasons. However, staining from rust and iron sediments can be challenging to clean.

It would be best if you got rid of the toilet stains. You can also use homemade ingredients. They create an eco-friendly and effective solution that is free from chemicals.

According to Bob Vila, a home improvement expert, cleaning your toilet regularly may extend the life of the toilet.

It is advisable to apply the detergents and solutions when the toilet bowl is completely dry to achieve satisfactory results.

Ensure that the water is shut off at the fixture shutoff valve of your toilet. Flush the water inside the bowl to drain it completely. That way, the hard stains will not be covered in water.

Applying the solutions and detergents in exposed stains will act efficiently because they will be stronger.

It is important to note that you should not use a metal scrubbing brush to clean your toilet. Metal leaves scratch marks on the toilet bowl. They are not easy to remove in a white toilet bowl.

Some of the solutions you can use to remove stains include;


Are you sick of cleaning stains from your toilet bowl using harsh abrasives and cleansers with strong smells? Try using vinegar solution.

It cleans the yellow stains perfectly with the help of a toilet brush. Place three cups of vinegar directly into the toilet bowl. You can also use a spray bottle and spray it directly into the bowl while scrubbing it.


Bleach is one of the strong cleaning agents. Put half a cup of dry bleach powder into the toilet bowl. Allow it to sit for a while, then scrub it off using a toilet brush.

Borax Powder

Borax powder is hardly sold in supermarkets because it is a powerful cleaning agent. It can only be found in hardware stores.

You should shut the water supply into the toilet tank and empty the bowl by flushing it when using borax powder.

Sprinkle the powder directly on the stains inside the toilet bowl. Scrub them off using a toilet brush. Let the powder sit and reconnect the water into the tank. Flush it to check if the stains are clean.

Trisodium Phosphate

According to Somil Mehta, a researcher/author, “Mineral Scales and Deposits, 2015, trisodium phosphate is good for getting rid of stains.

Add a tablespoon to 1 gallon of warm water to use trisodium phosphate. Mix it properly and soak a cloth on the solution. Use it to rub the stain until it is clean.

Here is a table that represents what others have tried to remove the yellow stains in toilet bowls:

Method Used by Forum Members Online to Remove Toilet Bowl YellowingPercentage of total responses
Iron out which is a strong product that must be added to the toilet bowel. Let it sit and then flush the toilet. It is strong in odor, so be careful.17
Pumice Stone can remove yellow stains in a toilet. It does not scratch, and it is non-toxic. I recommend the long-handled pumice stone, click to see it on Amazon.34
The WORKS – amazing on yellowed toilets according to forum members. I recommend the two-bottle pack of the WORKS that is available on Amazon (click here).17
Citric Acid – some dish soaps contain citric acid that you can try to get rid of bowl stains.33
data derived from forums on housecleaning tactics  

My Toilet Tank Water Is Brown, But When I Flush, The Water Is Clear, What Is Happening

It is not a wonder that your toilet tank water might appear brown, but the water is clear when flushed.

What happens is that the tank walls have accumulated rust making the water look brown. The browning in you see could be an optical illusion

Optical illusions create an image that is deceptive or misleading to the brain. The brown color could be on the floor of the toilet tank, making the water inside look like it is brown.

All that is an optical illusion because the water comes out clean once you flush the toilet. The brown color appears when the iron in water oxidizes after exposure to oxygen.

What Exactly Is Oxidation?

Oxidation can be defined as the loss of electrons during an ion, Molecule, or atom reaction.

The iron that exists in water can be hazardous. When exposed to air, the water first turns cloudy t followed by a reddish-brown substance.

The sediment is usually a dangerous substance that is an oxidized or ferric form of iron. It dissolves completely in water.

How to get rid of oxidized iron from water

The step of oxidation can either be achieved by catalytic media. It can also be attained through chemical injection or aeration. Once the iron gets to a ferric state, it can be easily filtered.

The other option is passing water through a cartridge by backwashing the filter and then adding a water softener. Remember, water with iron sediments is already hard water.

Is It Safe to Shower in Yellow Water?

Any water discoloration should be an indicator that something is wrong somewhere. In this case, yellow water from your shower or bath tab is a sign.

It indicates that there could be iron in your water or rust in your pipes.

Bathing in yellow water is typically safe. Always check with your plumber for any issues that may be underlying.

The plumber can run a quick test to determine the root of your problem. A solution will be found to help get your water clear again.

Our skin is sensitive, and it is advisable to check the reason for water discoloration before using it.

To be safe, always perform a water test before using that water to shower or consume. If the yellow color turns brown, that means it’s hazardous to use it.

The yellow color in your shower means iron in the water. It also means that the pipes that pass water to your shower head on tap are corroded.

There could be the presence of calcium buildup in the pipes too. As I mentioned earlier, no problem lacks a solution!

Final Thoughts

It is good to stick to a cleaning routine for your toilet. That helps to avoid repeating the same process of getting rid of the yellow stains in the toilet bowl.

If the stains persist after cleaning your toilet, consider replacing the water pipes and the bolts. Also, get to the water source and soften the hard water if possible.

Related topics are why does my toilet whistle and why is my toilet bowl empty even if it seems to be working. Plus, it my toilet making noise because the concept of can you flush hair down the toilet in the bathroom.

Aron Blake

I am the lead copywriter on Homezesty and the Webmaster. I have a lot of experience in home renovations and the creation of style. I enjoy writing and sharing my tips on how to create the best living environment. My Linkedin Profile, My Twitter Account

Recent Posts