How to Sanitize a Hot Tub Without Overusing Chlorine

Chlorine plays a key role in keeping your hot tub water free of harmful bacteria and algae. However, too much chlorine can cause skin and eye irritation, unpleasant odors, and damage to spa surfaces.

Downsides of Overusing Chlorine

• Can dry out and irritate skin and eyes

• May lead to strong chemical smells

• Can degrade spa covers and equipment over time

• Upsets water balance, making maintenance harder

Alternative Sanitizing Options

Thankfully, you can maintain a clean and safe spa without overloading it with chlorine.

Bromine

• A popular alternative that is gentler on skin

• Works better than chlorine in hot water

• Requires regular testing and adjustment

Ozone Generators

• Produces ozone gas to kill bacteria and contaminants

• Reduces the amount of chlorine or bromine needed

• Still requires some sanitizer for residual protection

Mineral Sanitizers

• Use silver or copper cartridges to inhibit bacterial growth

• Lower chlorine demand while keeping water clean

• Easy to install and maintain

UV Systems

• Ultraviolet light destroys bacteria and viruses

• Often paired with a small amount of chlorine or bromine

• Helps keep water clear and safe

How to Properly Sanitize With Less Chlorine

Using alternative methods and good practices allows you to keep chlorine levels low while maintaining safe water.

Regular Water Testing

• Use test strips or a test kit at least twice a week

• Monitor chlorine, pH, alkalinity, and sanitizer levels

• Keep chlorine between 1–3 ppm for minimal irritation

Balance the Water Chemistry

• Maintain pH between 7.2 and 7.8

• Alkalinity should stay within 80–120 ppm

• Balanced water helps sanitizers work more effectively

Shock the Water Appropriately

• Use non-chlorine shock treatments weekly to break down contaminants

• Oxidizes organic matter without raising chlorine levels significantly

Clean and Maintain the Hot Tub

• Wipe down surfaces regularly to prevent buildup

• Clean or replace filters monthly

• Drain and refill every three to four months

Tips for Preventing Contamination

Encourage Cleanliness

• Have guests shower before entering

• Avoid lotions, oils, or cosmetics in the water

• Keep pets out of the hot tub

Cover the Spa When Not in Use

• Helps keep debris, insects, and contaminants out

• Preserves sanitizer levels by reducing UV breakdown

Maintain Circulation

• Run the pump daily to ensure even distribution of sanitizers

• Use the jets occasionally to keep water moving

Advanced Practices

Use Enzyme Treatments

• Help break down oils and organic contaminants naturally

• Reduce sanitizer demand and prevent scum lines

Consider a Saltwater System

• Generates chlorine from salt automatically, but at a steady, lower level

• Feels softer on skin and requires less maintenance

Common Mistakes to Avoid

• Skipping regular testing and letting levels drop too low

• Relying solely on one method without backup sanitation

• Adding too much chlorine “just to be safe”

• Neglecting to clean filters and surfaces regularly

Helpful Notes

• Keep a maintenance log to track chemical adjustments and cleanings

• Store all chemicals properly to prevent spills or contamination

• If you notice persistent cloudiness or strong odors, reassess water balance and cleaning routines

By combining smart maintenance habits and alternative sanitizing methods, you can enjoy a clean, healthy hot tub without overusing chlorine.