Can Too Much Chlorine Damage a Hot Tub?

Chlorine is essential to having a healthy and safe hot tub experience, but it can be a dangerous chemical if not used correctly. Will a little extra chlorine damage a hot tub?

Consistently having too much chlorine can damage a hot tub by corroding pipes and eating away at acrylics, such as the filter as well as also causing health problems. Unlike a swimming pool, a hot tub has a relatively small volume of water, so it is easy to overdo the chlorine level if you are not careful. Knowing how much chlorine to use and what issues it may cause is crucial to having a safe hot tub.

So, how much chlorine is too much? Just what are the effects of too much chlorine? And how can we adjust the chlorine level if it’s too high? Continue reading as we take a deep dive into the effects of chlorine on you and your hot tub and just what to do if you made a boo-boo. 

That being said, there is more to the picture. We’ll talk about the specifics of how it damages your hot tub, what health issues it could cause, how much chlorine to use, and other extremely important knowledge, so keep reading.

Can Too Much Chlorine Damage a Hot Tub

Too much chlorine can damage a hot tub

People often don’t bother to pay any mind to the amount of chlorine they are putting into their hot tubs, but that’s a big mistake. While chlorine is a regularly used chemical and is safe in small amounts, it must be used properly. Too much of the chemical could cause issues for both you and your hot tub. 

The overuse of chlorine can cause multiple issues with your hot tub, costing you quite a bit of money in repairs:

  • A high level of chlorine may throw off the pH levels in the water, creating a high level of acidity, corroding any metal pipes carrying water to the unit. 
  • High levels of acidity can also eat away at acrylic surfaces, filters, and pillows. Spotting the damage is easy; darker surfaces will become bleached and soft surfaces will harden and become brittle. 

Thankfully, if you realize your mistake soon enough and fix it, the likelihood that your tub will sustain any actual damage is low. Most of the issues occur when a hot tub is consistently over-chlorinated.

You should not panic though if your chlorine levels are normally correct and then suddenly you find they are high, perhaps because you added too much in one go. Damage will occur to your hot tub over time if the chlorine levels are consistently high. If it just an unusual situation that last just a few days then don’t worry about it.

Too much chlorine can also damage you

Another, and more important, reason to make sure you aren’t using too much chlorine is your own health or that of your family.

If you exceed the safe limit of chlorine (2-4 parts per million), then do not get in until you are sure that the levels have gone down. There can be a serious side effects that you don’t want to even take a chance with. 

Exposure to high levels of chlorine can cause several ailments such as:

  • Asthma attack 
  • Lung Irritation 
  • Skin Irritations 
  • Eye Irritation
  • Hot tub rash (see CDC’s advice on hot tub rash)

In rare cases, you may also experience:

  • Vomiting
  • Throat Irritation or burning
  • Dizziness
  • Shallow breathing
  • Coughing
  • Even chest pains

So, if you are experiencing any irritation of the eyes, skin, or lungs, you need to hop out and check the chlorine levels immediately. 

How much chlorine is too much?

To figure out how much chlorine you should use, you have to measure it by parts per million. To get this measurement, you’ll need to pick up a reliable test kit. They are simple to use and you can find them at any pool store or department store that carries pool supplies.  

When testing your chlorine levels, you should see between 1.5 and 3ppm and the water in the tubes should be clear. The amount of chlorine additive you need will change based on the manufacturer, and you should always check the manufacturer’s guidelines before adding chlorine to your hot tub. 

On average, you’ll need to add a teaspoon of chlorine per every hundred gallons. Make sure that you add your chlorine to the hot tub while it’s circulating to help raise the chlorine levels quickly. That will ensure that your readings are more accurate and you don’t overdo the chlorine. 

How to lower the chlorine level in the hot tub

If you find that your chlorine levels are high, it’s not the end of the world. There are a few ways that you can correct this easily:

  • You can let the hot tub deal with the issue on its own. If you aren’t planning on hopping right in, just let it sit for a day or two and come check levels. You can speed up the process by turning on the jets and removing the cover. It isn’t the fastest way, but it is the easiest and cheapest solution. Just be careful not to continuously overdo it because that is when you’ll start seeing damage to the hot tub. 
  • Another good option might be to just drain the hot tub and start again. This method is still a little time-consuming but doesn’t require anything extra.
  • If you need a quick fix, then find a chemical neutralizer that can bring the chlorine levels down to where you need them. The chemical you need is called Sodium Thiosulfate. While this may be the fastest way to knock the chemical levels down, it isn’t the best, and you should only use it if you have to bring down the chlorine quickly, perhaps if you have friends coming round to use it.

These three solutions should get you back on track with no issues. Ensure that if you have the time to let the hot tub deal with itself and that it isn’t happening consistently. 

How often should you maintain your hot tub?

How often should you maintain your hot tub?

It’s not a bad idea to get into a routine with your hot tub maintenance so that you can make sure that you’ve always got just the right amount of chlorine in your hot tub. 

To keep it at the proper levels, it’s not a bad idea to add chlorine every two or three days, if that is what the water test suggests (ie. chlorine levels are low). You should also perform weekly maintenance on it to make sure you don’t have any damage occurring. This should include:

  • Clean your filter and remove any debris that might have accumulated.
  • Check your pH and alkaline levels, being sure that they are between 7.2 and 7.6.
  • Check your chlorine levels; you should have a pretty good idea of where they are if you’ve been keeping up with them.

You can also prevent damage by changing the water every few months or so and soaking the filter. Wear and tear will happen, but if you take these few precautions, you’ll be able to minimize and catch issues before they turn into real problems.

Hot Tub Maintenance Course

I bought this course some months after I bought my first hot tub and was struggling with maintaining it. It was money well spent.


If you do accidentally overdo your chlorine, don’t worry about it too much. It will go down with time, and you’ll only need to worry about whether excess chlorine damage a hot tub if you make that mistake regularly.

If you need a quicker solution, then you can drain the tub and refill it, or purchase a product meant to neutralize chlorine.

Here are a couple of things to do that will help you minimize damage to your hot tub from chlorine:

  • Get a good test kit and test the water every two or three days.
  • Don’t allow your chlorine levels to go over 3 ppm. 
  • Ensure that you are doing regular maintenance on your hot tub (that includes checking any pipes susceptible to corrosion). 
  • Create a schedule and stick to it!

Keeping up with your chlorine levels is very important. If they start to exceed acceptable levels, fix it as soon as possible to avoid further damage to your hot tub.