How to Lower Chlorine In Your Pool (4 Tips)

how to lower chlorine levels in pools

We’ll admit it — keeping the chemicals balanced in your pool isn’t always the easiest thing to do. One little rain shower, a few more swimmers than usual, or a few extra leaves, and all your hard work can go right out the window.

Chlorine levels, in particular, are extremely important for the safety and cleanliness of your pool water. If it’s low, your pool can quickly become something more like a swamp than a fun place to hang out.

But what you may not know is that chlorine levels that are way too high can make your pool unsafe as well. It can cause things like damaged airways, lungs, and skin.

Now, don’t panic and go drain your pool and ditch the chlorine altogether. Chances are your levels are not high enough to cause any of that as long as you’re checking it regularly and not adding too much. 

Besides, you’ll probably smell it before it becomes a problem!

But if you do notice the levels starting to creep up and you can’t seem to get it under control, there is a solution.

What Should Chlorine Level Be in Pool?

You’ll often see us mention that it’s important to keep your chlorine levels between 2 and 4 ppm (parts per million) with the ideal level being 3 ppm.

Anything within this range is safe, but if it starts moving out of those parameters, it’s important to address it immediately.

How to Tell If Your Pool Has Too Much Chlorine

Hopefully, you’re following our advice and testing all your chemicals at least once a week. If so, you’ll be able to see if your chlorine levels are too high right away.

But other things can happen to cause it to get too high and you may not realize it until you get in the pool.

Everyone’s sensitivity to the chemical is a little different. Some people notice itchy eyes or skin with as little as 5 ppm. Others might not notice it until it’s much higher.

If anyone complains of these symptoms, get everyone out of the water and test it immediately.

Smell is also a good indicator. If the levels are too high, almost everyone will notice the strong bleachy smell. 

But keep in mind that there could be other reasons for the smell other than high levels. Sometimes it’s an indication of chlorine lock.

That also needs to be addressed quickly, but it usually means your chlorine is too low. 

Why is My Chlorine Level So High?

Overdosing your pool with chlorine is actually fairly easy to do, especially if you’re not testing regularly. 

Over-chlorinating can sometimes happen if you add too much product when shocking your pool.  It can also happen if you have a problem with your liquid chlorine pump or leave it running too long. 

Or you might simply mismeasure during regular maintenance.

What Happens If Chlorine Levels Are Too High?

High chlorine levels can be problematic, but it’s usually not an emergency situation unless they start climbing way above the ideal range. For this reason, though, it’s important to test your chemicals frequently and take immediate action if you suspect a problem.

Most of the time, the only thing that happens with high chlorine levels is itchy skin and eyes. But that depends on exactly how high they are. And that’s tough to say because everyone reacts differently.

As much as we hate to get all serious, you do need to be aware of some scary things that can happen. 

For one thing, ingesting or inhaling too much chlorine can lead to chlorine poisoning. Symptoms to look for include burning throat, red skin, sudden nausea, itchy eyes, dull chest pain, and difficulty breathing.

Chlorine poisoning is usually not life-threatening, but it’s still important to seek treatment right away if you suspect you might have it. This is especially true for children.

Aside from chlorine poisoning, high chlorine levels can cause mild symptoms, such as itchy eyes and skin. It can also throw off your other chemical levels, making it hard to get them balanced.

How To Lower Chlorine Levels in Pools: 4 Tips

There are several ways to lower the chlorine levels in your pool. None of them are too difficult but it may take a little patience and perseverance on your part.

  1. Drain some of the water and replace it with fresh water.

This should help to give you a fresh start, but if the levels are still a little too high, you can try another method or leave it alone for 24 hours and test it again. 

UV rays will burn up some of that chlorine naturally.

  1. Add hydrogen peroxide.

You can actually use drugstore grade 3% hydrogen peroxide for this at 2 ounces per 100 gallons. 

A better option is a product made just for pools with the appropriate percentage of H2O2 for this use. One is Aqua Silk’s Oxidizer. 

  1. Add ascorbic acid.

Ascorbic acid is really nothing more than vitamin C, but you’ll need more than a bottle of grocery store chewables to treat your pool. The commercial products contain a blend usually intended to remove metal stains from your water. 

This product will also quickly burn off a lot of that extra chlorine. Just follow the instructions for the appropriate dosage.

  1. Add sodium thiosulfate.

Most chlorine neutralizers contain sodium thiosulfate, which will instantly drop your chlorine by about 1 ppm with each dose.

  1. Allow nature to work.

Sometimes the best course of action is no action at all. Simply turn on your pool pump and let the sunlight and aeration naturally kill off the chlorine.

Chlorine Alternatives to Sanitize Your Pool

Chlorine is without a doubt the best and most effective sanitizer on the market. However, there are several reasons why some people go another route.

Some people are just more sensitive to the stuff than others, for example. And some people just prefer using something a little gentler. 

Whatever the reason, there are a few other things you can try.


Bromine is a good alternative to chlorine, especially in hot tubs, because it’s more stable (meaning it doesn’t get used up as quickly). It’s gentler on sensitive skin and puts off less odor than chlorine. 

It’s important to note, however, that bromine is still chlorine-based. So if you’re allergic to chlorine, this is not the solution for you.

It also doesn’t oxidize the water as well as chlorine.


A mineral system is a much more natural way to sanitize your pool than using chemicals. They use copper and silver to kill germs and prevent bacteria.

These are great for making your water soft and keeping it clean. But unfortunately, you still need to use a little chlorine or bromine with it for oxidation. You just won’t have to use nearly as much as when you use the chemicals alone.


An ozonator is a machine you attach to your filtration system that inserts ozone into the pool water. This reacts with any contaminants and kills them off.

Chlorine Levels FAQ

Can you swim if chlorine levels are high?

It’s definitely not safe to swim if your chlorine levels are too high. It can irritate your skin and eyes and sometimes cause chlorine poisoning. 

Check your chemical levels at least once a week to avoid problems. And if you have already had issues with unbalanced chemicals, check them daily until you get it under control.

How long does it take for chlorine levels to go down?

This depends entirely on which method you use. 

Sodium thiosulfate is probably the quickest fix, with other chlorine reducers right behind it.

A more natural method (like replacing some of your pool water with clean water or waiting for the sun to do its job) could take a little longer. 

Sunlight might take at least 24 hours to decrease the chlorine levels, depending on how high they were to start with. 

But if you drain some of your pool water, you can check it as soon as it’s refilled. Sometimes that’s all it takes to do the trick.

Should I shock pool if chlorine is high?

The purpose of shocking a pool is to raise the chlorine to a super high level to destroy any contaminants you haven’t been able to kill. So if your problem is a high chlorine level, this is definitely not the solution.


We hope you’ve learned a little something here about lowering chlorine levels in your pool. While this is not the most common problem with pool chemistry, it’s certainly something that can happen.

The most important thing to remember is that you should be testing your chemicals weekly and making sure your chlorine stays very close to 3 ppm. And the second it gets too far away from that number, do something about it.

Keep all swimmers out of the pool until you correct the problem and pay close attention to your usual dosage.

Safe swimmers are happy swimmers!

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