ACE® Salt Water System


You've got questions? We've got answers!

Answers to the most frequently asked questions about the ACE® Salt Water System are listed below.


How much salt is in a salt water hot tub with the ACE system? Will the water taste salty?

The ACE system requires very little salt. It is estimated that humans can taste salt in water at approximately 3,000-4,000 ppm. The target salt level when using the ACE system is only 1,750 ppm. Take a look at how the salt level of hot tub water treated with the ACE system compares to the average salt level of other liquids.

LiquidAverage Salt Level
Sea Water35,000 ppm
Tears6,000 ppm
Salt water pool   3,000-5,000 ppm
ACE spa water1,750 ppm

How often do I need to add salt to my hot tub?

The ACE system will continually generate chlorine from the salt initially added to the water. The hot tub owner only needs to add more salt when they drain and refill the hot tub, or after topping off the water significantly.

What is Active Oxygen?

Active Oxygen is a term used to describe a powerful oxidizer (OH-) derived from water (H2O), and is different from oxygen (O2) derived from Ozone (O3).

How is Active Oxygen created in my hot tub?

Active Oxygen is created when energy transferred into the water breaks apart water molecules. Without the diamond electrode there is not enough energy to split apart water and create Active Oxygen — no other hot tub salt water chlorine system can create this oxidizer.

What makes Active Oxygen so special?

The benefit of Active Oxygen is that it breaks down waste and contaminants completely with oxygen, leaving behind carbon dioxide and water. It does not leave behind chloramines or other byproducts that can cause hot tub water to be irritating to the skin and eyes or cause a strong odor.

Is the ACE system technology used anywhere else besides hot tubs?

This process, called advanced oxidation, is used to treat water in a variety of other industries. It's also used to purify ground water and waste water, as well as to treat water used in food manufacturing facilities and in breweries, to name just a few other applications.

Why is calcium hardness a concern for hot tubs?

The accumulation of scale caused by high levels of calcium hardness can be detrimental to hot tub components like the jet pumps and heater, as well as to the electrodes within the ACE system. All hot tub owners can benefit from the Vanishing Act® calcium remover, which helps to protect hot tub components and makes hot tub water feel softer.

How can I decrease calcium hardness in hot tub water?

The Vanishing Act calcium remover is the best option for decreasing hot tub water hardness levels and achieving the ACE system's recommended calcium hardness level (50 ppm) for improved operation and minimized cell cleaning. Removing calcium from the hot tub water reduces the need for additional chemicals, like Stain and Scale, which only temporarily treat calcium in the water.

I have very hard water; what's the best way to fill my hot tub?

The On The Go portable hot tub water softener is an effective and cost-efficient way to avoid issues that can result from having high levels of calcium hardness. The On The Go can be used to fill and top off the hot tub with soft water, and again when you eventually drain and refill your hot tub. The On The Go can be reused and recharged over and over again, so it will last the life of your spa.

What if my calcium hardness levels are high in my hot tub?

If scale does accumulate on the ACE system electrodes, it can easily be removed by soaking the ACE cell in a simple solution of pH Down and spa water for 10 minutes. An empty bottle with cell cleaning instructions on the label is included with the ACE kit for convenience. The cell should be cleaned this way once every three months as preventive maintenance. FreshWater® cell cleaning solution is also available.

How often do I need to change my hot tub water with the ACE hot tub salt water system?

The number of water changes needed per year varies by owner. The ACE system helps reduce the amount of bottle products that are added to the water and breaks down waste and contaminants completely. In doing so the system helps minimize the level of total dissolved solids in the water, helping hot tub water to last longer — up to 12 months.

How long does the ACE cell last?

The cell is designed to run for a finite number of hours; the ACE cell does not operate 24 hours a day. The amount of time the cell is working each day is determined by the size of the spa and how often it's used, so the life of the cell will vary. On average, the cell will last between 2 and 3 years.

Does the ACE system cost more than other hot tub water care systems?

Over time, we estimate the cost of water care using the ACE system to be slightly more than traditional approaches to hot tub water care. However, the ownership experiences provided by the ACE system are very different. The ACE system eliminates the need to manually dose the hot tub water with sanitizer, and eliminates side effects associated with spa water care. Your Hot Spring

Which hot tub models are available with the ACE hot tub salt water system?

The ACE salt water sanitizing system is compatible with all new Hot Spring Highlife® Collection, Highlife Collection NXT and Limelight® Collection spas.