The contaminants notorious for causing brown stains in toilet bowls are iron, manganese and sulfur. These pollutants can also produce iron bacteria, manganese bacteria and sulfur bacteria, which also can produce brown stains.
Citric acid
More importantly, it's probably even more effective than vinegar for getting rid of that brown stain in the toilet. Simply pour a kettle of almost boiling water into the bowl, follow up with 250ml of citric acid, and leave it for some hours – preferably overnight. The next day, scrub and flush.
Or perhaps you are seeing some black stains in your toilet bowl or dishwasher? These unsightly stains may be a result of high levels of manganese in your water. Manganese is a natural element that is commonly found in water, soil, and some foods and, at appropriate levels, plays a role in keeping us healthy.
One of the most obvious signs of hard water buildup is in the toilet. You might see a white or rust-colored ring forming at the waterline or staining at the base of the bowl.
Brown stains are the result of hard water and not your cleaning wrongly. Don't use bleach as it will only bleach out the stain, but not remove it. Use a clean brush with plastic bristles.
The carbonic acid that is in coke is what helps to clean toilet stains. Picture the acidity slowly working its way through the stains, melting them away. It can take a while depending on how stubborn the stain is which is why it's vital to have a suitable cleaning method depending on how bad the toilet condition is.
To prevent calcium carbonate from piling up into your cistern, pour a single cup of white vinegar into it. The mixture should be three parts white vinegar to one water. After you pour it into the cistern, mix it slowly and carefully until it's evenly distributed.
If you get brown stains in your toilet bowl, the good news is that it's not caused by anything that you, ahem, do in the bathroom. It's actually due to high concentrations of minerals in hard water, like calcium, iron, and manganese, that build up inside the toilet bowl over time, according to Hunker.
White crusty deposits that may accumulate around the toilet bowl, the end of a faucet or showerhead or appear as water spots come from water rich in the naturally-found calcium or magnesium minerals often referred to as water hardness.
Let It Sit For 12 Hours
Leave the vinegar and water mixture in the toilet tank for 12 hours without flushing the toilet. This is why this cleaning process is best done overnight, as you are less likely to need the bathroom throughout the night than during the day.
As a one-stop cleaning solution, pour one cup of bleach around the bowl. Then tackle every inch with a toilet brush or a handheld scrub brush. Let it sit for five minutes, then flush.
WD 40 is great for cleaning out keyboards or loosening bike chains – but did you also know it is really good at removing limescale from your toilet? While it can be put to a number of helpful uses around the home, WD 40 is particularly good at softening rust and limescale deposits in the toilet (and bathroom).
Grab some gloves and use a Magic Eraser to go to town on toilet bowl stains. Some users even recommend cutting a piece off and letting it dissolve the bowl to remove that unsightly ring all on its own.
Leaving bleach in a toilet overnight is fine, but you shouldn't leave it any longer, or else it might corrode your toilet. If you do decide to leave it in the bowl overnight, let other members of your household know so that they don't use the toilet and accidentally mix the bleach with ammonia from urine.
White Vinegar and Baking Soda
The best way to clean stubborn stains in your toilet is with baking soda and vinegar. Sprinkle a good amount of baking soda inside the bowl, then spray on the vinegar until it starts foaming. Wait ten minutes, then scrub the bowl vigorously with a toilet brush.
Grab some white vinegar and pour around 130 ml of the vinegar down the toilet. Shut down the lid. Leave the toilet overnight – about 8 hours is enough. If you find that you've still got stains around the rim, drape some vinegar-soaked toilet paper around the rim.
If the clog still seems to be intact, start over at step 1 and repeat the process a couple of times. For extra-stubborn clogs, you can let the fizz mixture sit overnight or combine this method with plunging.
Hard Water Mineral Buildup. If you regularly notice brown water inside your toilet bowl, it could be due to hard water mineral buildup. Hard water contains high levels of minerals like magnesium, calcium, and iron that can build up over time inside your pipes and fixtures.
Toilet bowl stains can form because of hard water mineral deposits, stain-causing bacteria, rust, and other substances that get stuck to the sides of the bowl.
"The biggest don't when it comes to toilet tanks is bleach—do not use bleach or products containing bleach inside the tank, as it can corrode the internal parts of your toilet. If you are aiming to remove tough stains from the tank, I also recommend white vinegar diluted with water."
Vinegar and baking soda produce that oh-so-familiar chemical reaction that powers through buildup and loosens tough stains. While it might seem like it's chewing its way through grime, it's not powerful enough to damage the porcelain finish of the toilet bowl.
Vinegar is safe and milder than caustic cleaners designed for the toilet, and those commercial cleaning agents can eat away the good bacteria in your septic system. To safely and inexpensively clean your toilet bowls, pour a generous glug of vinegar, followed by a heavy sprinkling of baking soda, into the bowl.