One of the best upgrades you can add to any hot tub is a Corona Discharge Ozone System. When paired with a traditional sanitizer, ozone helps you enjoy cleaner, clearer water with fewer chemicals.

Ozone doesn’t replace chlorine or bromine — but it is a powerful partner that destroys unwanted contaminants in your water. In this article, you’ll learn what ozone is, how it works, and why it’s one of my preferred systems for maintaining a healthy hot tub.

🌬️ What Is Ozone?

Ozone (O₃) is a powerful oxidizer that neutralizes:

• Germs
• Viruses
• Bacteria
• Bodily fluids (sweat, saliva, urine)

Ozone is simply oxygen with three atoms instead of two, giving it strong sanitizing power.

There are two types of ozone systems used in hot tubs:

Corona Discharge Ozone (CD Ozone)

This is the system we recommend. It is more advanced, produces higher concentrations of ozone, and is far more effective in moving water.

UV Ozone

Uses ultraviolet light to create ozone.
However:

• It produces very low ozone output (typically 0.5% or less)
• Requires long exposure time
• Is less effective in fast‑moving water

For modern hot tubs, Corona Discharge is the superior choice.

⚙️ How Ozone Works in Your Hot Tub

Ozone is injected into the water as tiny bubbles during a low‑speed filtration cycle or through a dedicated circulation pump. The smaller the bubbles, the more effective the ozone.

Because ozone takes time to contact all the water in your spa, it cannot be your only sanitizer. Instead, it:

• Reduces the amount of chlorine or bromine you need
• Prevents biofilm buildup in plumbing lines
• Helps remove minerals and dissolved solids by clumping them together for filtration
• Breaks apart combined chlorine/bromine, freeing your sanitizer to work more effectively

The result?
Cleaner water, fewer chemicals, and less maintenance.

🛠️ How Do I Add Ozone to My Hot Tub?

Most modern hot tubs can accept an ozone system. It includes:

• An injector plumbed into the return line
• The ozone generator, usually a small black box connected to the control board

Your spa’s control system must support ozone so it can turn the generator on and off automatically.

🧪 What Chemicals Should I Use With Ozone?

The ideal pairing is:

• Granular chlorine
• A mineral stick (optional but highly recommended)

This combination kills bacteria quickly, then allows ozone to maintain clean water between uses.

How to Use It Daily

After each soak:

1. Add one teaspoon of granular chlorine per person.
2. Run a clean cycle or run jets on high for 10 minutes.

The chlorine sanitizes immediately, then gets used up. By the next day, your water will be clean and chlorine‑free, and ozone takes over from there.

To handle lotions, soaps, and personal care products, add a non‑chlorine shock or enzyme weekly.

📉 Do I Need to Maintain a Chlorine Level?

If your ozone generator is functioning properly:

• It’s normal for your test strip to read 0 chlorine
• You only need chlorine after each use

For peace of mind, you may maintain 0.5–1.0 ppm, but it’s optional.

If you go weeks without using your hot tub, add a healthy chlorine dose once a week. Ozone works slowly, so weekly sanitation prevents contaminants from taking hold.

🧂 What If I Use a Salt System or Bromine?

Ozone works with other sanitizing systems:

• Chlorine
• Bromine

The same rules apply:
You only need to add sanitizer after use or weekly if the spa sits idle.

🔄 When Should I Replace My Ozone Generator?

Ozone generators typically last 3–5 years. Here’s how to tell if yours is failing:

💡 Ozone Indicator Light

Some units have a light or faint vibration sound.
However, lights can show “power on” even when ozone is not being produced.

🫧 Bubbles at the Ozone Jet

Tiny bubbles (<1 mm) are good.
Large bubbles are usually just air.
Note: Some systems always show bubbles even when ozone output is zero.

👃 The Ozone Smell

A fresh, rainstorm‑like scent when you open the cover after hours of being closed is a good sign.
You can also sniff the ozone hose (before the check valve) to confirm output.

🧪 Ozone Test Kit

Single‑use kits can confirm approximate ozone production.

🌫️ Poor Water Quality

Cloudy water, algae, or increased chemical demand may indicate ozone failure — after ruling out:

• Dirty filters
• Low pump run time
• Poor water balance
• Lack of sanitizer
• No shock treatment

📚 Additional Ozone Facts

• Hot tub ozone is safe when installed correctly.
• Ozone has the same fresh smell as after a rainstorm.
• The word “ozone” comes from the Greek ozein, meaning “to smell.”
• High ozone levels can shorten the life of covers and pillows — open the cover every few days to vent.

🚀 Next Steps

Ready to upgrade your hot tub experience with cleaner, fresher, lower‑chemical water? A Corona Discharge Ozone System is one of the most effective enhancements you can add.

Visit your local dealer or check online for a compatible ozone generator.
Your hot tub — and your skin — will thank you.