Oxygen Hot Tub Maintenance Guide & Schedule

You’ve heard about using chlorine or bromine to sanitise your hot tub water, but have you heard about using active oxygen? Dive into our guide to find out everything you need to know (and more) about using oxygen in your hot tub or swim spa. 

Jump to a section:

What is an oxygen hot tub sanitiser?

Active oxygen is the perfect sanitiser alternative to chlorine and bromine for people with sensitive skin as it’s a milder solution. It’s also typically odour-free.

How do oxygen tablets work?

Oxygen tablets work in conjunction with oxygen liquid to kill bacteria and make the water safe for bathers.

Safety: Oxygen, chlorine, and bromine

You should never mix sanitisers as they can cause a dangerous chemical reaction.

If you’re considering switching sanitisers, you should drain and clean your hot tub, including the pipes, with a pipe cleaner. You should not use the same dispensers, even if you’ve cleaned them thoroughly, as contamination can occur.

How much oxygen should I add to my hot tub water?

Check the water’s oxygen levels are between 5-10mg/l using oxygen test strips. Weekly, you need to add one 20g oxygen tablet along with 15ml of oxygen liquid per 1,500 litres of water. You also need to add one tablet before each use and ensure the range is between 5 and 10 parts per million.

Top tip: 1mg/l = approximately 1ppm (parts per million).

Using the test strips, you should also check the pH level and total alkalinity. The pH should be between 7.2 and 7.6 and you can use a pH increaser (pH+) or pH decreaser (pH-) to balance the levels. The total alkalinity should be between 80 and 120ppm. Find out more about balancing the pH and total alkalinity in our guide.

How do I shock my oxygen hot tub water?

Remove the thermal cover and turn on the jets. Then, add 35g of chlorine shock per 1500 litres of water and leave for at least an hour. This must be done at least once a week and can also be performed after using your hot tub if the water is cloudy. The chlorine shock will re-activate the oxygen in readiness for your next dip.

Please note: Using a non-chlorine shock in an oxygen hot tub will not sanitise the water. You must use chlorine shock.

If the water becomes cloudy, foamy, or green, you can check out our guide.

Oxygen hot tub maintenance schedule

See our handy maintenance schedule below to learn which tasks to perform and when:

Daily maintenance

1. Test the oxygen level in your hot tub to ensure it’s between 5-10 ppm.
2. Prior to bathing, add one 20g oxygen tablet per 1,500 litres of water.

Weekly maintenance

1. Remove the hot tub filter and hose off any debris. If required, use a filter cleaner to prevent a build-up of grease. We recommend purchasing a spare filter, allowing you to rotate them and increase their lifespan. Check out our guide on cleaning a hot tub filter for more information.
2. Once you’ve popped the filter back into the housing unit, ensure the hot tub cover is removed and switch on the pumps. Add one 20g oxygen tablet and 15ml of oxygen liquid per 1,500 litres of water.
3. Check the pH level is between 7.2 and 7.6 using test strips. If needed, use a pH increaser or pH decreaser to balance the water.
4. Ensure the oxygen level is between 5 and 10 mg/l. If it’s below this level, add another oxygen tablet.
5. Shock your hot tub water by adding 35g of chlorine shock per 1500 litres of water. Leave it uncovered with the jets running for at least an hour.
6. Finally, if you live in a hard water area, add 23ml of No Scale per 1,500 litres of water to help prevent limescale build-up.

Quarterly maintenance

1. Remove and clean the filters, following our step-by-step filter cleaning guide.
2. Drain the hot tub completely, clean it, and fill it with fresh water. See our hot tub cleaning guide for more information.
3. Balance the pH using either pH increaser or pH decreaser to achieve a level between 7.2 and 7.6.
4. To sanitise the fresh water, add two 20g oxygen tablets and 60ml of oxygen liquid per 1,500 litres of water.
5. If you live in a hard water area, adding 38ml of No Scale per 1,500 litres of water will help prevent limescale build-up.

Parting advice

To browse our hot tub oxygen range, click here. We recommend that you always read the chemical guidelines provided by your hot tub manufacturer. 

Need more advice? Give us a call on 01482 212322 or email enquiries@outdoorlivinghottubs.co.uk and we’ll help you out. Or drop in and see us in our Hull or Leeds showrooms to see our hot tub chemical range for yourself. 

Not near one of our Yorkshire hot tub showrooms? No problem, if you’re looking for a new hot tub you can explore our virtual showroom or book a video call with our showroom team.

Stay up to date with our latest products, hot tub guides and updates on Facebook or Instagram.