Hot Tub & Spa Care 101

There isn't much that's better than relaxing in a hot tub or spa after a stressful day at work, a hard workout, or just a weekend indulgence. No matter the season, owning a hot tub or spa is a real treat. While hot tub/spa maintenance may seem complicated, it is pretty straight-forward once you know the basics.

The most important elements of hot tub/spa maintenance are:

Leslie's Water Circulation and Filtration

Leslie's Water Testing

Leslie's Pool Cleaning

Circulation and Filtration

Circulation helps to keep your hot tub/spa clean by regularly passing water through the filter. The more your water circulates the cleaner it will remain.

Your hot tub/spa may have an automatic circulation schedule that runs once or twice a day for a set period of time — usually 15-20 minutes. If your hot tub/spa does not have an automatic cycle, manually run it twice a day for 15-20 minutes for optimum cleaning. With regular circulation cycles, your pump will not have to work as hard as it would if it had to clean several days of accumulated contaminants.

DIY TIP: Make sure that your equipment is in good working order by following the manufacturer’s guidelines for routine maintenance and filter cleaning.

Water Balance and Sanitation

Hot tubs/spas use chemicals faster than pools — 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/spa will keep your water safe and clean!

Like pools, hot tub/spas can use either chlorine or bromine for sanitation.

Using Chlorine

Chlorine is less expensive, but you will use more of it. Due to the high temperature of hot tub/spa water, chlorine loses efficacy faster than bromine. Chlorine is an economic and effective choice for sanitizing your hot tub/spa, and using it correctly is simple.

  • After filling your hot tub/spa, shock the water with a dichlor shock, such as Leslie’s Chlor Brite. Shocking raises the amount of chlorine in your water, which increases Free Available Chlorine (FAC) levels to destroy bacteria and algae. Follow the label directions for the shock dosage amount. Test the water after shocking and do not enter the water until the FAC level is 2-5 ppm.
  • After the initial shock, keep your FAC levels around 2-5 ppm; add more chlorine as needed to maintain those levels. If your Cyanuric Acid (CyA) level is 50 ppm or higher, maintain a minimum FAC of 3.0 ppm.
  • Test the FAC levels before and after hot tub/spa use the first few times, then test weekly thereafter. Establish the amount of dichlor needed to keep FAC levels of 2-5 ppm and then adjust dosage as needed.
  • When you use your hot tub/spa frequently — or have heavy bather load — use shock to bring the FAC level back into range. Test frequently to ensure FAC is above zero (0).

Using Bromine

Bromine lasts significantly longer than chlorine and is more expensive, but because it sanitizes more efficiently, you use less.

  • After filling your hot tub/spa, you will create a bromide reserve by adding sodium bromide to your water. Bromine needs this reserve of sodium bromide — plus an oxidizer, such as shock — to work efficiently.
  • After creating a bromide reserve, shock your hot tub/spa with chlorine or a non-chlorine oxidizer, such as Leslie's Fresh 'N Clear. Follow the label directions for the chlorine shock dosage amount. Test the water after shocking and do not enter the water until the Total Bromine level is 4-6 ppm.
  • There are two different ways to maintain proper bromine levels. Add bromine tabs using a bromine dispenser, or apply bromine as well as an oxidizer such as chlorine. With either method, bromine levels need to remain around 4-6 ppm.
  • Using bromine does not eliminate the need to shock your hot tub/spa. You will still need to shock the water on a weekly basis to burn off organic contaminants. After shocking the water, wait for Total Bromine levels to drop below 4-6 ppm before entering the water.
  • Test the bromine and pH levels every time you plan to use your hot tub/spa. Test weekly for Total Bromine, pH, Total Alkalinity (TA), and Calcium Hardness (CH). Cyanuric Acid (CyA) does not affect bromine systems, so there is no need to test for it.

Balancing Water

  • Test for CH — the ideal level is 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 can damage your hot tub/spa or spa.
  • Test for TA — the ideal level is 80-120 ppm, based on the type of sanitizer. If the TA level is low, use Leslie's Alkalinity Up to raise it. If TA levels are high, add Leslie's Dry Acid to lower it.
  • Test for pH — the range should be 7.2 to 7.8. To increase pH, add Leslie's Alkalinity Up; to lower it, add Leslie's Dry Acid. If you have difficulty maintaining the correct pH level, consider using a product such as Liquid Spa pH Up when refilling your spa with water. This product stabilizes the pH and controls water balance, making maintenance easier. Aeration will also increase pH levels. Test pH before and after use to understand how the chemical levels change based on use.

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

DIY TIP: Have the make and model of your specific hot tub/spa available. This will make it easy to find your maximum water capacity, maximum occupancy or weight limits, and essential components.


Although chemicals do their part to sanitize your water, they cannot remove larger particulates or build up on the sides and floor. That is where cleaning comes in.

Hot water causes users to release more body oils and waste into the water, and can also increase algae and bacteria growth. This makes it even more important to perform regular skimming and brushing, along with water balance and sanitation. Manual spa vacuums also work well.

Regular manual cleaning will keep your water cleaner and healthier and allow your pump to do its job moving water through the filter.

DIY TIP: Because of the higher water temperatures, hot tubs/spas require more frequent monitoring.

If you follow these basic practices and maintenance, you will be able to enjoy your hot tub/spa year round and well into the future.

And remember ... at Leslie's, we’re here to help you create a safe, sanitary, and perfect hot tub/spa experience.