How to Use Chlorine in Hot Tubs

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Shock your hot tub after having 3 or 4 people in it at once.
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Spas and hot tubs are like swimming pools in that they need chemicals to control the level of algae and bacteria in them. Bromine is the preferred hot tub sanitizer but is more expensive than other options. To cut costs, hot tub owners often use chlorine instead. It's important to maintain the correct amount of chlorine in your hot tub, just as it is in a pool. If the chlorine level is too low, the spa won't be sanitary. If it's too high, the excess chlorine will dry out your skin. A weekly check of your spa lets you maintain the proper chlorine levels on an ongoing basis. You will need to shock your hot tub, however, after heavy usage and when opening it for the season.

Routine Maintenance

Things You'll Need

  • Chlorine test kit

  • Sodium dichlor chlorine

  • Bucket

  • Measuring spoon

Step 1

Test your spa water at least once a week using test strips. Your free chlorine level should be between 3 and 5 parts per million. If it is higher, leave your hot tub uncovered, and simply wait for the chlorine level to come down. This may take a few days. If it is too low, follow these steps to add chlorine.

Step 2

Verify that you have the correct type of chlorine for spa use. Sodium dichlor works best in hot tubs, because it has a neutral pH and does not require the use of a chlorine stabilizer.

Warning

Always use dichlor and never trichlor in your hot tub. Using pool chlorine rather than hot tub chlorine causes problems and voids your hot tub warranty.

Step 3

Turn the hot tub on. The water from the jets will help circulate the chlorine you will be adding. You want the water jets on, but leave the air off, because this encourages chlorine gases to escape.

Step 4

Calculate how much chlorine you need to reach the desired chlorination level. Measure out 2 teaspoons of chlorine for every 200 gallons of spa water. Add the chlorine to a bucket of water to dissolve, and then pour the bucket into the hot tub.

Step 5

Allow the hot tub to run for two hours and then check the free chlorine levels again. Add more chlorine if needed, and repeat the process. After chlorinating your spa a few times, you'll get a good idea of how much chlorine to add each week.

Shocking

Things You'll Need

  • pH test kit

  • pH adjustment chemicals

  • Sodium dichlor chlorine

  • Scale or measuring spoon

  • Bucket

  • Chlorine test kit

Step 1

Check the water's pH level and adjust it as necessary. When shocking a spa, the pH level should be between 7.2 and 7.4.

Step 2

Turn your hot tub's water jets on, but leave the air off.

Step 3

Calculate how much chlorine (sodium dichlor) you need. The goal of shocking is to temporarily increase the free chlorine level to 10 ppm. Shocking a hot tub requires about 2 ounces (4 tablespoons)of chlorine for every 500 gallons of water.

Warning

Always carefully read and follow the instructions on your product when adding chlorine to your hot tub. This will help prevent overchlorination from keeping you out of your hot tub any longer than necessary when shocking.

Step 4

Dissolve the desired amount of chlorine in a bucket of water, and then add the water to your hot tub. You can turn the spa off a few minutes after adding the chlorine, but leave it uncovered for at least 30 minutes.

Step 5

Do not use your hot tub until the chlorine level drops back down to 5 ppm.

references

Home is where the heart is, and Michelle frequently pens articles about ways to keep yours looking great and feeling cozy. Whether you want help organizing your closet, picking a paint color or finishing drywall, Michelle has you covered. If she's not puttering in the house, you'll find her in the garden playing in the dirt. Her garden articles provide tips and insight that anyone can use to turn a brown thumb green. You'll find her work on Modern Mom, The Nest and eHow as well as sprinkled throughout your other online home decor and improvement favorites.

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