Don’t Leave CLR in Toilet Overnight: Know The Danger
Do not leave CLR in your toilet overnight. Although CLR is an efficient toilet cleaner, its acidic nature causes damage to the surface if you leave it for longer. Follow the steps to effectively use CLR in a toilet.

- Wear rubber gloves
- Shut off the water supply
- Remove the water from the bowl, and pour 1 cup of CLR into the bowl.
- Once the stains are removed, restore the water supply and flush to remove the CLR.

Avoid mixing cleaning agents with other chemicals, which can be hazardous and cause property damage.
That’s not all. Keep reading the article to know what will happen if you leave CLR in the toilet overnight.
Can You Soak Your Toilet in CLR Overnight?
You should never keep CLR in the toilet bowl for over 2-5 minutes, let alone overnight.
There is a big misconception that the longer you keep CLR, the more it’ll clean the surface. That is completely wrong.

CLR is acidic, so it works well, but if left on surfaces for too long, it can cause damage. After two to five minutes of contact, rinse with cool water.
Is CLR Dangerous To Use?
Lactic acid makes up 8–12 percent of CLR. It can harm different surfaces because it is highly corrosive if left on for an extended period of time. So be careful about the time length when leaving CLR on surfaces such as,
- Wood
- Clothing
- Wallpaper
- Carpeting
- Marble
- Colored grout
- Terrazzo
- Natural stone
- Painted or metallic glazed surfaces
- Plastic laminates
- Formica, aluminum, or any other surface that is damaged or cracked to avoid Bath Fitter Mold Issues.
After using CLR, wear rubber gloves and thoroughly rinse the area with cold, clean water. Never mix CLR with bleach.
Toxic fumes will be released when mixed with bleach! The CLR Material Safety Data Sheet contains information about all the risks and first aid procedures.
So make sure you are completely safe when you are using CLR. It is your responsibility to store them safely, making sure your family members are safe.
How Do I use CLR to Clean a Toilet Bowl?
To get the desired results from CLR, you need to know how to use it on your toilet bowl which is full of stains. So here is how to use CLR in a toilet bowl.

Put on your rubber work gloves:
As CLR contains some chemical substances that can damage your skin and are somewhat toxic, you must use gloves when using CLR.
Cut off the toilet’s water supply:
To avoid washing out the added CLR, you have to cut off the toilet’s water supply. When it is stopped, wait for 2 or 3 for the bowl to dry out.
Remove the water from the bowl:
Then remove the water from the bowl using a sucker or any other practical method. You shouldn’t worry about the water that was in the bowl because it is highly contaminated.
Into a bowl, pour 1 cup of CLR:
After the water is removed, pour 1 cup of CLR into the bowl.


Allow two minutes:
Then the reactions will take place and will clean out the rust and the stains inside the bowl, making it a clean and shiny surface. So, for better results, wait for 2 to 5 minutes after pouring CLR into the bowl.
To remove the stains, use a toilet brush to clean the bowl:
To clean out the tough stains, use a toilet brush and scrub until the stains disappear.
Restart the water supply:
Then turn off the water supply and flush it away to remove the CLR compound from the bowl. If needed, brush the bowl again to get the best out of it.
Are There Any Alternatives to CLR?
If you are not able to find CLR, then there are some alternatives you can use that will do the job for you. Lemon juice and vinegar are two natural alternatives, but they simply don’t work as quickly or as well.
So, let’s see what are the alternatives to CLR.
Lime-A-Way:
Similar ingredients are used in CLR and Lime Away. The correct name is “Lime-A-Way,”. Anyway, in terms of the ingredients, CLR combines lactic acid, gluconic acid, and a few other solvents, while Lime Away uses sulfamic acid.


All you need to know is that they both effectively remove water stains and are designed specifically for them.
White distilled vinegar:
White distilled vinegar is one of the best homemade substitutes for CLR. All of the uses for vinegar outlined in the previous section are possible. Vinegar is entirely natural, works just as well, and costs half as much as other alternatives.
Frequently Asked Questions (FAQs):
Will CLR damage the PVC pipe?
All PVC products are safe to use with CLR products. Copper plumbing and septic tanks are also safe to use. However, CLR should not be used on painted surfaces, aluminum, etched glass, Formica, colored grout, natural stone, brass, and copper.

Is it safe to flush CLR?
As long as your home has a septic system, CLR is safe to flush. CLR is neutralized by water by the time it reaches the septic system.
Does CLR damage glass?
CLR can only be used on colored glass that has not been painted or coated after manufacture. You can use CLR as a diluted solution of CLR and warm water if you avoid touching the lead or frame of the stained glass.
Conclusion
So, be careful of the timing when you leave CLR in Toilet, especially overnight.
Also, be careful when mixing cleaning agents and other chemical solvents. They can be dangerous and cause damage to your property.
Hi, I’m Anna Jeffery, an experienced author and cleaning expert. I strive to share my knowledge with everyone by writing useful guides and tips to keep their living and working spaces clean and healthy. I believe everyone deserves to live in a clean and organized environment, and I take pride in knowing that my articles are helping people achieve that goal. Stay tuned for practical and useful cleaning tips!