The Ins & Outs of Hot Tub Care

Hot Tub Care

Hot tub care doesn't have to be difficult. Keeping a clean, well balanced hot tub is a lot like the maintenance on a swimming pool, just on a smaller scale. Hot tubs go through quicker chemical changes due to heat and aeration, so they require additional care and upkeep. Learning the ins and outs of the chemicals you need for a hot tub will keep your water safe and clean!


Hot tub care requires one of two primary chemicals for sanitation, chlorine or bromine. Chlorine tends to be less expensive, but requires more maintenance. Due to the high temperature of hot tub water, chlorine loses efficacy faster than bromine. That said, chlorine is still an excellent and popular sanitizer, and using it correctly is a simple task.

  • After filling your hot tub, shock your water with a dichlor shock, such as Leslie's Chlor Brite. "Shocking" adds an excess of chlorine to your water, raising Free Chlorine (FC) levels and destroying bacteria and algae. Test the water after shocking and mix in additional shock until you reach about 10 ppm of FC.

  • After the initial shock, you'll need to keep your FC levels around 3-6 ppm on a regular basis, adding more chlorine accordingly.

  • First time hot tub owners will want to test the FC levels before and after hot tub use on a daily basis. Veteran hot tub owners will want to test weekly. Remember, 3-6 ppm of FC is your goal. Once you've established the amount of dichlor needed to stay within this range, you can adjust the dosage as needed.

  • Make sure to account for heavy usage of your hot tub. For instance, if you have multiple people in the hot tub for an extended period of time, it's always a good idea to shock your hot tub afterwards to bring FC levels back up.

Note: If FC levels drop below 0, it creates a breeding ground for bacteria, among other problems. It's important to test your water on a regular basis to maintain a safe and trouble-free hot tub.


Bromine lasts significantly longer than chlorine, requiring less application and maintenance. This increased efficiency comes at a higher cost, but the extra expense can be well worth it. Whether convenience or price rules out the use of chlorine or bromine, maintenance and upkeep is still the key for effective hot tub care.

  • After filling your hot tub, create a Bromide Reserve. This can be quickly achieved by adding sodium bromide to your water. To be an effective sanitizer, bromine needs this reserve of sodium bromide, plus an oxidizer such as shock.

  • After successfully creating a bromide reserve, shock your hot tub. You will want to test and continue shocking the water until you reach about 10 ppm of bromine. Afterwards, wait until this level drops below 10 ppm before entering the hot tub yourself.

  • Upon reaching the proper bromine level, there are two different ways to maintain it. You can add bromine tabs with a bromine dispenser, or you can continue to apply bromine alongside an oxidizer such as chlorine. Either way, you'll want to keep bromine levels around 4-6 ppm.

  • Using bromine does not eliminate the need to shock your hot tub. You'll still have to shock the water on a weekly basis to burn off any organic contaminants. After each shock, wait until bromine levels drop below 10 ppm before reentering the water.

  • Using a test kit, test the bromine and pH levels every time you plan on entering your hot tub. Similarly, test for bromine, pH, TA, and CH on a weekly basis. CYA does not affect a bromine system and does not have to be tested.

Note: Whether or not you decide to sanitize your hot tub using chlorine or bromine, you will always want to drain and refill your hot tub every 3-4 months. This will keep the water clean and clear.

Balancing The Water

Pool water testing for safe water

The most important step in hot tub care is balancing your water. Keeping your water balanced ensures that the chemicals do their job and keep your swimmers safe. After acquiring a test kit, follow the steps below to test and balance your water. If you'd like, the experts at your local Leslie's store can also test your water completely free of charge.

  • First, test for CH, or Calcium Hardness. You want your levels to be at about 150 ppm. If your CH levels are below 100 ppm, add a calcium increaser such as Leslie’s Hardness Plus. Low CH levels can lead to corrosive conditions that damage your hot tub, and high levels will cause scale build-up.

  • Next test for TA, or Total Alkalinity. TA levels should be around 50 ppm. If your TA level is low, use Soda Ash to quickly raise the amount of TA in your water. If your TA levels are too high, adding Dry Acid will lower them to the right amount. It’s important to note that the aeration of hot tub jets will also lower TA levels. If you plan on running the jets, take this into account when balancing your TA.

  • Finally, test the pH level. It should be in the 7.2 to 7.8 range. To increase the pH level, add Soda Ash; to lower it, add Dry Acid. If you're having difficulty maintaining the correct pH level, consider using a product like Liquid Spa pH Up when refilling your spa with water. This stabilizes the pH and controls water balance, making maintenance easier. Don’t forget, aeration will increase pH levels and lower TA levels. It's a good idea to test pH before and after hot tub usage, so you can account for the chemical changes when using the hot tub.

Rest & Relaxation

Taking care of your hot tub can feel daunting at first, but keeping your water healthy is a snap with the right preparation. Chlorine and bromine will both do a great job sanitizing your water, and choosing between the two is largely a matter of your budget. The most important part of the process is testing your water on a regular basis to make sure the chemicals are balanced. If you're still unsure about the testing process, bring a sample of your water into your local Leslie's store; they'll test the water for you, for free! As long as you keep adding your sanitizer and testing the water on a regular basis, you can soak in good health for years to come.

Leslie's Free 10-Point Water Test

Recommended Products

Leslie's Spa Maintenance Kit

Spa Chemicals

inflatable hot tub

Inflatable Spas

hot tub cover

Custom Covers

Facebook  Twitter X  YouTube  Instagram
Leslie’s makes every effort to provide accurate recommendations based upon current ANSI/APSP/ICC-5 2011 (R2022) standards, but codes and regulations change, and Leslie’s assumes no liability for any omissions or errors in this article or the outcome of any project. You must always exercise reasonable caution, carefully read the label on all products, follow all product directions, follow any current codes and regulations that may apply, and consult with a licensed professional if in doubt about any procedures. Leslie’s assumes no legal responsibility for your reliance or interpretation of the data contained herein, and makes no representations or warranties of any kind concerning the quality, safety, or suitability of the information, whether express or implied, including, without limitation, any implied warranties of merchantability or fitness for a particular purpose.