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Does WD-40 Remove Hard Water Stains in Toilet? 4 Easy Steps

scrubbing toilet using toilet brush

When you have hard water, it can seem almost impossible to get rid of the stains in the toilet bowl. The residue left behind by minerals and other substances is almost impossible to remove. However, the good thing is that with a little work and some everyday ingredients from your pantry –like WD-40 – you can remove those stubborn stains in no time. Yes, WD-40 can help remove those toilet stains caused by hard water. Let’s discuss.

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What Is WD-40?

WD-40 is a multipurpose lubricant that comes in handy when trying to fix something. It works wonders on squeaky hinges, locks, and pretty much anything that moves or can be lubricated to reduce friction. One of WD-40’s most interesting uses is as a stain remover for toilets. So how do you use WD-40 to remove hard water stains in the toilet? Let’s discuss, but first…

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What Exactly Are Hard Water Stains?

Hard water stains are crystals that form on the surface of the metal, ceramic (which is what most toilets are made of), glass, and tile. They are caused by minerals in the water, such as calcium and magnesium, that attach to these surfaces.

The stains can range from light gray to black, and they can be found in most homes with a water source that contains minerals. The minerals attach themselves to your toilet, sinks, tubs, and other fixtures leaving behind a black or gray stain that is very difficult to remove. So, to remove the stain, you will need to use a cleanser that is stronger than the minerals in your water – and WD-40 fits the bill. Let’s look at how to use it to get rid of those toilet stains.

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The 4 Steps to Remove Hard Water Stains with WD-40

1. Apply the WD-40

close up hand spraying WD-40
Photo Credit By: Yevhenii Orlov, Shutterstock

Spray a small amount of WD-40 onto the stained area of your toilet, making sure to completely saturate a small section of the toilet at a time. The WD-40 will break down the minerals in the water and help lift them off of the surface.

2. Let the WD-40 Sit

Leave the WD-40 on the stained area for about 5-10 minutes. The longer the WD-40 sits, the better your results may be – particularly for older stains.

3. Scrub the Stain

After allowing the WD-40 to sit, scrub the stained area with a toilet brush to remove the mineral remnants.

4. Flush the Toilet

Close up flushing water in clean toilet bowl
Photo Credit By: SumanBhaumik, Shutterstock

Lastly, simply flush the toilet to rinse out the remaining WD-40. If needed, repeat the steps.

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Why Does WD-40 Work to Remove Hard Water Stains?

WD-40 is made up of a complex combination of hydrocarbon solvents that can break the chemical bonds holding minerals together. The solvents in WD-40 are made to break down substances like paint, dirt, and oil. They’re also able to break down the minerals found in hard water.

As mentioned earlier, hard water stains are made up of minerals that are bonded together. These minerals can be broken down by WD-40 and flushed away. And that’s pretty much the gist of it.

Side Effects of Using WD-40 to Remove Hard Water Stains

WD-40 is a quick and easy way to remove hard water stains, but honestly, it really isn’t a long-term solution. The stains will come back if the water in your home is still hard and unfiltered. It’s a good idea to use an anti-limescale spray (such as Lime-A-Way) that you can use on a regular basis to prevent the minerals in your water from building up again.

Also, note that WD-40 can be a bit messy to use. It can also leave a film on your toilet that will need to be scrubbed off. If you have a septic system, it’s not a good idea to use WD-40 to clean your toilet on a regular basis. The solvents in WD-40 can be harmful to the bacteria that help break down waste in the septic tank. So preventative measures are recommended by most plumbing experts.

WD-40 close up
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What Else Removes Hard Water Stains

If you’re looking for something more septic-friendly, you can use a commercial cleaner that is specially formulated to remove hard water stains. There are products like CLR that neutralize mineral buildup and dissolve minerals like rust, lime, and limestone.

When shopping for a commercial cleaner, make sure it has a high concentration of sodium hydroxide. This is the active ingredient that breaks down the minerals in hard water. And you can even make your own cleaner using baking soda, vinegar, and salt.

How to Prevent Hard Water Stains In Toilet

You can prevent hard water stains from forming in your toilet by installing a water softener. This will lower the amount of minerals in your water, which will help prevent stains from forming. You can also use an anti-scale spray to clean your toilet each time you flush.

This will help prevent the minerals from building up again. Another thing you can do is to simply clean your toilet more frequently. The longer you wait to clean your toilet, the more buildup there will be. It’s best to make it a part of your cleaning routine to clean your toilet at least once a week, especially if you have this issue regularly.

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Other Surprising Ways to Use WD-40

WD-40 has actually been a handy tool for tackling household tasks for decades. It’s no surprise that this all-purpose lubricant has found its way into many homes and workshops. From its ability to remove sticky residue to its power to keep pests away, WD-40 can do a lot more than just keep things running smoothly. Here are a few surprising ways to make your life easier with WD-40.

Defrosting Frozen Locks

Frozen yellow padlock
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If you have a car or outdoor storage lock that’s frozen in the winter, you can use WD-40 to defrost the lock. Simply spray some WD-40 on the frozen lock and let it sit for a few minutes. Next, use a paper towel to wipe away the grease from the lock to open it. You can also use WD-40 to protect locks from freezing in the winter. Simply spray some WD-40 on the locks and wipe them off with a cloth.

Preserving Leather Goods

If you own leather items like shoes or bags, you can use WD-40 to protect them from damage. To do so, just spray WD-40 on your leather items and wipe it off with a lint-free cloth (like microfiber). This will help keep the leather from drying out and cracking, and it can also be used to clean off caked-up or dried dirt/dust.

Removing Sticky Residue

man holding adhesive duct tape
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If you’ve ever used a product like duct tape and needed to remove the residue afterwards, you know how frustrating this can be. This is where WD-40 can make a huge difference. All you need to do is apply a little WD-40 to the sticky residue, let it sit for a few minutes, and then wipe it off with a paper towel.

The solvent in WD-40 will lift the adhesive off your skin or other surfaces so you can get rid of it with ease. WD-40 can also be used to remove sticker residue from glass, tile counters, and rubber.

Cleaning Stubborn Dirt

You can use WD-40 to remove the most stubborn dirt and grime off your tools and even your car. You can also use WD-40 to degrease your hands after a dirty gardening or car repair session. Or, if you have a really dirty floor or oil-stained upholstery, you can use WD-40 as a quick cleaner. Just spray on the fabric and wipe away the dirt with a clean rag (on upholstery, do a spot test first).

Oiling Squeaky Hinges

Door Hinges
Image Credit: Artsiom Kuchynski, Shutterstock

WD-40 is a great lubricant for squeaky hinges on doors, drawers, and other household items. Like with other applications, just spray the hinges with WD-40 and let it sit for a few minutes before wiping it off with a paper towel or some type of rag. If the squeaky door happens to be a part of your garage door chain, you can also spray the chain links (or rollers) with WD-40 and leave it to work its magic overnight.

Preserving Metal Tools

If you own an old tool that is made from metals like cast iron, consider using WD-40 to protect it from rust. It can typically be used on tools made from copper, brass, and other metals. And if you have a tool that’s already covered in rust, try spraying WD-40 on the tool and letting it sit for an hour or so to help loosen the rust and remove it.

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Hard water stains can be one of the most frustrating things to deal with when you have them in your toilet. Luckily, there are plenty of things that can be used as a cleaner to remove them. WD-40 is one of the most popular choices and it is also one of the easiest.

You can also use a commercial cleaner or make your own using baking soda, salt, and vinegar. Lastly, consider installing a water softener or cleaning your toilet more frequently to reduce the chances of hard water stains forming again.

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