What chemicals does a hot tub need?
A sanitiser, usually chlorine, and a way to keep pH in range. The CDC recommends at least 3 ppm of chlorine and a pH of 7.0 to 7.8. In the One Model, the salt system makes the chlorine, and the rest are household items: cleaning vinegar to lower pH and baking soda to raise alkalinity.
What does a hot tub need to stay clean?
Every hot tub needs a sanitiser in the water. Most use chlorine. The CDC says chlorine is added to kill germs, and that it does not work right away. For a hot tub, it recommends a level of at least 3 ppm.
That level does not stay put. The CDC lists things that use chlorine up: sweat and dirt from bathers, sunlight, and the droplets and mist that hot tub jets throw into the air. The King County public health hot tub guide (Seattle and King County, Washington) adds heat and bubbling water to the list. It says a hot tub uses up chlorine faster than a swimming pool does, which is why owners test.
What pH does a hot tub need?
pH is a measure of how acid or alkaline the water is. The CDC recommends a pH of 7.0 to 7.8 for pools and hot tubs. Staying in that range matters because pH changes how well chlorine works and how pipes wear.
As pH goes up, chlorine gets worse at killing germs. As pH goes down, pool and hot tub pipes are more likely to corrode or break down. The King County guide adds that high pH can also make the water cloudy.
If your water is outside the range, you adjust it. Products exist to raise pH and products exist to lower it. A pool supply store can advise on which one and how much, and the label on the product says how to use it.
Does a hot tub need cyanuric acid?
No. The CDC recommends not using cyanuric acid, or chlorine products that contain it, in hot tubs. Some chlorine products do contain it, so read the label.
In the One Model, the salt system makes the chlorine inside the tub, so there are far fewer chemicals to buy and handle.
How does the One Model handle chemicals?
The salt system makes chlorine from salt. An ozone chamber, a floating skimmer and an antimicrobial filter clean the water alongside it. All of it runs on the water pump, which works 24 hours a day. That is what Good Hot Tubs means by minimum chemistry: far fewer chemicals to buy and handle.
Your part is the weekly strip. You test the water, enter the result in the app (Gecko in.touch 3) and check the salt system's run time. The app shows what Waterlab reads in the plumbing, which is pH, ORP and temperature, and it tells you what the water needs. If the reading asks, you lower pH with cleaning vinegar or raise alkalinity with baking soda, and liquid chlorine can be used to shock the water. The tub starts on sea salt or a pool salt blend, so there are no specialty chemicals to buy.
What is in a hot tub start-up kit?
Good Hot Tubs has not decided yet whether a start-up kit comes with the One Model, or what would be in it. Steps and handrails cost extra, and the $19,995 CAD price covers the tub, its water-care system and app, the Smartop Upright 3.0 hard cover and standard delivery to your pad.
When you shop for any hot tub, ask the seller what the kit holds and what it is meant to cover. Ask whether it matches the way the tub makes its own sanitiser.
How do you handle hot tub chemicals safely?
The King County guide gives plain rules. Read the label on every product for its contents, storage and use. Never mix chemicals, not even different types of chlorine, because many are not compatible with one another. Use clean utensils to handle them, and wear gloves to keep them off your skin.
The King County guide does not recommend household bleach in a hot tub. It says bleach can raise the level of dissolved solids in the water and loses strength in storage. It also suggests checking with a store before using scents, salts or soaps in the tub, because they can upset the water's balance.
With a salt system, you handle fewer products. A local expert on Vancouver Island is the person to ask about the rest.
Questions
How much chlorine should a hot tub have?
The CDC recommends at least 3 ppm of chlorine in a hot tub. In the One Model, the salt system makes the chlorine and the app helps you keep track.
Can you use household bleach in a hot tub?
The King County guide does not recommend it, because it can raise dissolved solids in the water and loses strength in storage.
What happens if hot tub pH is too high?
The CDC says chlorine gets worse at killing germs as pH goes up. The King County guide says high pH can also cause cloudy water.
What chemicals does a saltwater hot tub need?
It still has chlorine, made by the salt system from sea salt or a pool salt blend. For the One Model, cleaning vinegar lowers pH, baking soda raises alkalinity, and liquid chlorine can shock the water.
Sources
General facts on this page come from these public sources. Facts about the One Model come from Good Hot Tubs.
- Home Pool and Hot Tub Water Treatment and Testing. U.S. Centers for Disease Control and Prevention (CDC).
- Staying Happy and Healthy in Your Hot Tub, sixth edition (PDF). Public Health, Seattle and King County.
Related answers
Is the One Model right for you?
Ten questions about your home and how you would use a hot tub. You see your result before you give any contact details, and you can ask for a test soak on Vancouver Island when you send it.