How Long After Adding Chlorine Can You Test a Hot Tub?


Generally, you should check your hot tub and test the waters prior to adding chlorine. If you have already done this, adding chlorine and bromine needs about 30 minutes to sit. Once you have added these beneficial chemicals, you can test your tub’s water again. 

But, some will argue for the best results; checking 24 hours later is beneficial. Because these added chemicals are highly concentrated, it may help and give you a better read if you wait longer to test your tub’s water. 

Image Credits
Culligan of Ontario / Google Stock Images

How Long Should Chlorine Last in a Hot Tub?

When you are adding chlorine tablets to your hot tub, then it will solely depend on their size to get a basic lifespan. For smaller tablets, around 20g, their effects will last three to seven days. All other tablets that increase in size will increase the number of days that they will last in your tub.

However, chlorine tablets will last anywhere from three to seven days before you need to test your hot tubs’ water and add more solutions. 

How Often Do You Put Chlorine in a Hot Tub?

Ensuring a clean hot tub is very beneficial. And, with a clean hot tub, comes with adding the necessary amount of chlorine tablets in a timely manner. Generally, you should put chlorine in your hot tub at least once a week. But, for many, adding chlorine to their hot tub happens once a day. 

But it’s important to note that this will depend on how often your tub is used, the size of your tub, and the amount of chlorine you add at a time. Finding the best routine for your hot tub care will vary based on each person and their own tub. 

Image Credits
Swimming Pool Company in Hickory, NC / Google Stock Images

Why Do I Have To Put Chlorine in My Hot Tub Every Day?

The function of placing chlorine in your hot tub is to get rid of bacteria and biofilm. Biofilm is a substance that is generally found on your hot tub’s shell and will cause issues down the line with your hot tub’s plumbing and water filtration. 

Ultimately, chlorine is considered to be one of the most important sanitizers that can be used in hot tubs and pools. If your tub needs chlorine every day, it simply means that you are using your hot tub to its maximum potential, and bacterial, and biofilm needs to be taken care of. 

Adding chlorine to your hot tub every day isn’t negative; it just means that chlorine is doing its job. Or, on the other hand, if you add chlorine to your hot tub once a week, it simply means that chlorine is still working but doesn’t need to be as much as in other homeowners’ tubs. 

Can You Over Chlorinate a Hot Tub?

However, if you add chlorine to your tub every day, other problems could occur. Adding too much chlorine is another serious issue that many hot tub owners could face. The saying less is more applies to situations involving your hot tub and chlorine. 

Image Credits
Aqua Rec’s / Google Stock Images

Yes, of course, it’s possible to over-chlorinate your hot tub. This can happen by adding the incorrect amount of this chemical to your tub, or by being off in other cleaning solutions, and needing to overcorrect by adding too much chlorine.  


  • Jason

    Jason is an experienced writer, having contributed to many popular websites over the years. He currently writes for Big Hot Tub, a blog about everything hot tubs. When he's not writing or working on his blog, Jason enjoys spending time with his wife and two young children.