How Much Chemicals to Use When Refilling a Hot Tub

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Hot tub maintenance is important to your health. Bacteria can grow in warm spa water that is not properly treated with the correct chemicals. Your hot tub should be drained and refilled every three to four months. Clean your hot tub with a sponge and bleach mixed with water, rinse with a hose, and dry with clean towels. When you refill the hot tub with fresh water, it must be treated with a balanced mixture of chemicals. Testing the water with a test kit will tell you when your chemicals are balanced and your hot tub is properly protected.



Several types of chemicals are used to maintain a hot tub. Chlorine tablets are used as a sanitizer in a floating feeder, as are bromine tablets, nuggets, or crystals. Riguanide is non-chlorine, non-bromine sanitizers that kills bacteria. Ozone is used with ozonator equipment and reduces the amount of sanitizer needed. Spa minerals are used in a floating feeder that slowly releases the minerals and will lower the amount of sanitizer needed. Shock oxidizers are used to oxidize the water; they prevent cloudy water and eliminate body oils, dead skin, and cosmetic products and lotions.


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Testing Kit

Home testing kits are available and will serve as a guide to the balance of your hot tub water. Testing reveals your hot tub pH balance and alkaline levels. You will need a home testing kit to proceed with refilling your hot tub; these are available where you buy your spa chemicals. Pool and spa chemicals come in complete kits that are used for refilling your spa and it will take a lot of guesswork out of using the correct amount of chemicals.


When maintaining your spa, most home repair stores provide a water tester in the pool and spa chemical aisle. Take a sample of your hot tub water and the tester will tell you what is out of balance and what kind and how much of a chemical should be added.

How Much Chemical to Use

Many brands of spa chemicals are available and hot tubs come in different sizes. The amount of chemical depends on the chemicals you have purchased. The label will have detailed directions for how much shocker, sanitizer, chlorine tablets, and all other chemicals to use for a refill. Purchase a refill kit from your spa supplier; this will include all the chemicals you need and make this process easy. Test your water, following the testing directions and suggested levels information on the label.



Clean your hot tub filter with professional filter-cleaning products each month. Clean your hot tub cover monthly with cleaning solution that has UV protection to protect from sun damage.


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