Family Of 5 Pseudo vs. Chemical Dermatitis

by Jeff

I am not a first time user/ owner of a hot tub. I owned one several years ago and spent probably an hour in it every night. The chemical I used was a bromine sanitizer it kept me busy chasing correct values, but never an issue. We moved new place had no hotub purchased new hot tub. It has an ozonator and to reduce chemical use.

I have tried the silver cartridge/MPS for sanitation. I experienced a rash last year pretty bad actually. We are a family of 5 and of course I am concerned because my kids 3 girls age 5-10 are always in it. Neither my wife , my kids or any of our friends have had any problems. We have even had kid hot tub birthday parties.

I went to the Dr. He cultured the some of the areas testing for pseudo or staph. The results came back negative. There was never any sign of infection just lots of itchy bumps. The tub has set empty over the summer. It did have a super shock with chlorine then buffer of hydrogen peroxide and then drained wiped down and cleaned inside out. Recently set up the tub the entire family got in by next morning I had several bumps scattered mostly on my legs. No one else had any problems.

Could this problem be do to the MPS? I know it's supposed to be effective and less harsh at controlling contaminants than chlorine which many I have read have more problems with.

At a loss do not want this to effect anyone else in the family but miss the use of the tub as I said all values are okay the water smells clean and is crystal clear as well. I run pump everyday per manufacturer direction for the sanitizer.

Please help

Thanks for the question Jeff

I'm not a doctor so I won't give you medical advice on how to treat your condition. I'll give you my take on the situation you described and you can give that to your doctor for evaluation.

MPS doesn't kill bacteria, it oxidizes the bacteria and organic matter in the hot tub. Silver does kill the bacteria, but does it slowly.

Chlorine is good to kill bacteria in a hot tub but the organic material (sweat, lotions, spit) can build up quickly in a smaller area like a hot tub so using MPS can help. By using MPS the chlorine demand will be lower since it doesn't have to oxidize as much bacteria.

The problem with using chlorine in a hot tub is that chlorine breaks down very quickly at higher temperatures. This is why many hot tub owners opt to use bromine.

I believe the MPS dosage is one pound per 10,000 gallons. You can scale that down according to the size of your hot tub. It could be as simple as a slight overdose of MPS.

Ozone tends to oxidize chlorine turning it into chlorates. You can also take a little time and look up chlorites. Chlorates are oxidizers and should be kept away from organics or easily oxidized materials.

When you introduce silver and ozone along with organic bacteria there's alot going on with oxidation and chemical reactions. This could be the issue. You may be having a reaction to the mixture of ozone, MPS, silver, and organic matter as it's being oxidized.

Again, I'm not a doctor and this is not to be considered a medical evaluation of your condition.

Now, what to do about it? You can switch back to bromine. As the question said, you chased the chemicals but was able to dial them in right and didn't have an issue. Obviously this is a personal decision you need to make.

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Hope this helps.


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