Metal finishing Q&As since 1989

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Does 35% H202 need to be stabilized for a hot tub? If so, with what?

2006

I want to use hydrogen peroxide as a sanitizer for my hot tub so I don't have to use Chlorine. What makes H202 volatile? Does 35% H202 need to be stabilized and if so with what?

Also does anyone know how man ppm's I should keep the H202 at to keep the hot tub water from getting gross?
Thanks,

Mike Smitt
Hot Tub user - Jupiter, Florida

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Hi Mike,
Check out the website www.agriorganics.com, it will give you all the info you need. Good Luck!

Mark Baker
Process Engineer - Syracuse, New York
2006

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2006

'Hot Tub Chemicals 101' doesn't mention hydrogen peroxide. Consider other non-chlorine alternatives. http://www.hottubliving.com/spa.aspx

"Can H2O2 be used for disinfecting my pool or spa?
By itself, H2O2 is a rather poor microbiocide compared to chlorine, bromine, ozone, and other commonly used disinfectants. Consequently, it is not approved by regulatory agencies as a stand-alone treatment in these applications. However, there are a number of technologies which use H2O2 as part of the treatment program.
...
Concentrations > 8% H2O2 (by weight) are classified Oxidizers and are not recommended for household use. See Safety and Handling Guidelines"
--- From FAQs at http://www.h2o2.com

Don't worry about stabilizing hydrogen peroxide, that is for the manufacturers. Greater stability would make it less effective as an oxidizer. Just take precautions -- store in the original plastic bottle, avoid contact with metals (especially rusty steel), and follow the handling guidelines.

Forget ppm's, measure the oxidation-reduction potential (ORP). Buy a handheld ORP tester for $75 (works with any oxidizer). At pH 7.5, the recommended ORP is 700 milliVolts (mV). From
'ORP TESTING AND CHEMICAL AUTOMATION FOR SWIMMING POOLS AND SPAS,' NATIONAL ENVIRONMENTAL HEALTH ASSOCIATION,
http://www.energistx.com/water/neha90.pdf

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.