Can Pool Chemicals Be Used for Hot Tubs?

You’re digging through storage and realize you’re out of chemicals for your hot tub. You’d like to use it in the next day or so but all you have left are pool chemicals. As you compare the pool chemicals and hot tub chemicals, the ingredients seem exactly the same. What is there to worry about if you use your pool chemicals in your hot tub? You simply adjust the measurements because a hot tub is a smaller and hotter version of a swimming pool, right? WRONG.

This mistake may save you some money off-the-bat, but it can cost you a fortune in the long run. To put it shortly, no you shouldn’t use pool chemicals in your hot tub. Putting pool chemicals in your hot tub will greatly mess with the hot tub pH. An imbalanced pH of your hot tub can cause damage to your hot tub and make the lounging experience for bathers anything but relaxing.

If both chemicals are the same product, why do they create such unpleasant results? The difference lies in the differences between pools and hot tubs.

Pools vs. Hot Tubs

There are many differences between pools and hot tubs that can cause chemicals to create sharp spikes or drop-off in pH levels. The major ones include:

Size: This kind of goes without say. Pools are obviously larger than hot tubs. Swimming pools need larger amounts of more concentrated chemicals to effectively clean and treat the water which has more volume and covers a larger area than that of a hot tub. Hot tubs don’t only need less chemicals to treat, but their small size and area means the chemicals need to be more diluted to maintain the proper pH.

Water temperature: Swimming pools have a maximum water temperature of 80 degrees Fahrenheit. Hot tubs, on the other hand, typically have a temperature of between 95-120 degrees Fahrenheit. The hotter temperature affects the reaction of the chemicals, resulting in unexpected, erratic pH imbalances.

Jets vs. no jets: Water circulation helps disperse chemicals so less is needed and less concentrated chemicals are required. Pools, with more stagnant water require more chemicals that are higher concentrated.

Person capacity: The average hot tub bather capacity is around three, while a backyard pool can accommodate up to 300 bathers. With hot tubs, there are less bathers and the bathers don’t rotate in and out as frequently as those enjoying a pool. The less activity means the water pH is more susceptible to sharp spikes and drop-offs if the exact chemical measurements aren’t added or if the chemicals are slightly more or less concentrated.

Water evaporation: Water in a hot tub evaporates quicker than water in a swimming pool. When more water is being evaporated, the less chemicals are needed to do the job.

What Happens if Pool Chemicals Are Used in Hot Tubs?

Against what would seem to make sense, you shouldn’t use pool chemicals in your hot tub. Pool chemicals are more concentrated than those made for hot tubs, even though they are the same material. Here are some reasons to avoid putting pool chemicals in your hot tub:

• Pool Tri-chlor tablets are very acidic. While it doesn’t negatively affect pool water, its acidity rapidly destroys the hot tub’s water’s total alkalinity’s buffering capacity resulting in a severe drop in pH.

• Soda ash can also disrupt the alkalinity of hot tub water which can lead to a great spike in pH. The pH can potentially reach as high as 13, making it hazardous to soak in. It can be hard to restore perfect pH balance afterward even with adding acid to lower the pH.

• Liquid chlorine contains a lot of salt. In fact, there is one pound of salt per one gallon of chlorine. This high amount of salt added to such a small volume of water will increase the water’s alkalinity, pH and water hardness. These will cause the level of dissolved solids in the water to also increase. The abundant dissolved solids mean more frequent draining and changing of the water, increased scale and possible filter and equipment failure.

As with any big investment, hot tubs require a lot of time and costs to maintain and keep clean. The costs, however, is worth it. It’ll help protect your hot tub so you can enjoy it for years to come. Don’t skimp for cheap hot tub chemicals or try to substitute them with pool chemicals. If you have questions about your hot tub chemicals or general maintenance, feel free to contact Sunplay today!