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.
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.
A much better solution is to use some WD-40 Multi-Use Product. Most people don't know that WD-40 can solve many of their household cleaning needs quickly and easily. When cleaning a toilet bowl, WD-40 works by softening the rust and lime deposits, so they can be easily wiped away. You don't need to use much of it.
Simply wait and let the Coca-Cola work its magic in your toilet bowl. Just leave it in the toilet for at least 2 hours, though overnight is better. This gives the Coke more time to eat away at the unsightly stains in the toilet bowl.
The brainiacs behind this method explain it like this – you can clean your toilet using cola because cola is acidic. Whether you're using the big brand stuff or the store-bought cheap stuff, it doesn't matter – any dark, sugary, carbonated drink would do.
Steps to Remove the Cola Stain:
Make a solution of 1 part vinegar to 1 part water. For old or more serious cola stains, use a stronger vinegar solution or plain vinegar. Dampen a cloth with the mixture and use the cloth to dab the mixture onto the stain.
I did two 30-second intervals for 1 cup of Coke. You want to coat the entire toilet bowl with Coke. It'll run down and mix with the water, but leave behind an invisible layer of acid residue. The hardest part is letting the Coke work its magic.
Remove grease stains from clothing
That said, Coke has grease-busting abilities, too, thanks to the phosphoric acid in the drink. All you need to do is pop open a can of cola and pour it in with your laundry, along with the normal dose of detergent and run a wash cycle.
Because Coca-Cola contains carbonic, citric, and phosphoric acids, it's great for tough stains and dissolving rust.
Blot with a white paper towel to remove as much of the stain as possible, then neutralize with a white vinegar solution (1/3 cup WHITE vinegar in 2/3 cup of water). Saturate spot with white vinegar solution, using a spray bottle and blot to remove excess moisture.
It's dark brown, sticky and full of sugar: a perfect combination for a sticky stain. Get into action right away and no one will ever know that something was spilled there. Don't stress, with just a few easy steps you should be able to get the coke stain out of the carpet without much hassle.
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.
The acids in Coca-cola, coupled with the long sitting time, slowly works to lift stubborn stains and build up, which will then be flushed down during the clean up process. If you hate cleaning toilets, and would rather not touch the toilet bowl, then this cleaning hack is for you.
Descaling your kettle of limescale has never been easier thanks to Coca-Cola. Just boil a kettle full of Coke and leave to stand for 30 minutes. While other cleaning products may do a better job of restoring a shine to the showerhead, Coca-Cola can effectively unclog the head when other products fail.
Q: What happens to Coca-Cola when you open it and leave it out for a few days? A: It doesn't rot. It contains far too much phosphoric and citric acid for bacteria to grow. All the bubbles go out of it and it very slowly begins to oxygenate, which may change the flavor after about four or five days.
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.
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.
If you feel like it's your only option, though, start with diluted oxygen bleach and move on to chlorine bleach if necessary. Really old, stubborn stains sometimes respond best to liquid glycerin. Rub it in, let it soak and then launder again.