The Darkest Hour Is Just Before Dawn

[TomC]

Hi Guys,

We are about to turn the hot tub into a planter. Can't get the water right, skin rash, unbelievable frustration.

For those of you following along, I have developed a rash and I have been trying to sort of what is causing it. We have ruled out bacteria.

I thought it could be an allergy to MSP so we stopped using that, no improvement. Then we noticed the pH was 8.2, brought that down, maybe slight improvement but not certain (it did have promise though). Then last night I tested for cya and noticed there was none. Long story short, I went to the poolcalculator and determined that I needed to add 1.2 oz stabilizer for a 418 gallon tub. Added the stabilizer, waited 3 hours, jumped in and basically had a wild reaction to the water. I tested the water and the pH has plummeted to 7.2 and there is no measurable chlorine FC or TC. Adding the cya was a huge mistake. One dealer had no idea what cya was and said try it, the other dealer said don't do it. We did, *sigh*.

So, we are going to dump the water on the weekend and start over. The sad thing though is that we don't even know what starting over is anymore. Our dealer tells us one thing, we read another, honestly, kudos to all of you who can get it right.

Oh yeah. being a salt water tub just seems to make it even harder to deal with. Are there any Arctic Spa owners out there, with a chlorine system that can shed any light on our plight?

Thanks for Listening...Tom

[James Keirstead]

Hi Guys,

We are about to turn the hot tub into a planter. Can't get the water right, skin rash, unbelievable frustration.

For those of you following along, I have developed a rash and I have been trying to sort of what is causing it. We have ruled out bacteria.

I thought it could be an allergy to MSP so we stopped using that, no improvement. Then we noticed the pH was 8.2, brought that down, maybe slight improvement but not certain (it did have promise though). Then last night I tested for cya and noticed there was none. Long story short, I went to the poolcalculator and determined that I needed to add 1.2 oz stabilizer for a 418 gallon tub. Added the stabilizer, waited 3 hours, jumped in and basically had a wild reaction to the water. I tested the water and the pH has plummeted to 7.2 and there is no measurable chlorine FC or TC. Adding the cya was a huge mistake. One dealer had no idea what cya was and said try it, the other dealer said don't do it. We did, *sigh*.

So, we are going to dump the water on the weekend and start over. The sad thing though is that we don't even know what starting over is anymore. Our dealer tells us one thing, we read another, honestly, kudos to all of you who can get it right.

Oh yeah. being a salt water tub just seems to make it even harder to deal with. Are there any Arctic Spa owners out there, with a chlorine system that can shed any light on our plight?

Thanks for Listening...Tom

Hey Tom,

Stabilizer is not necessary in a spa, as Cyanuric Acid is to keep sun light (UV light) from breaking down the free chlorine in the spa. As a spa is covered much of the time it is not needed. Cya creates other issues in such a small bather load as well.

Feel free to contact me and I will be happy to help you work this issue out.

Kind regards,

James

[TomC]

Hi Guys,

We are about to turn the hot tub into a planter. Can't get the water right, skin rash, unbelievable frustration.

For those of you following along, I have developed a rash and I have been trying to sort of what is causing it. We have ruled out bacteria.

I thought it could be an allergy to MSP so we stopped using that, no improvement. Then we noticed the pH was 8.2, brought that down, maybe slight improvement but not certain (it did have promise though). Then last night I tested for cya and noticed there was none. Long story short, I went to the poolcalculator and determined that I needed to add 1.2 oz stabilizer for a 418 gallon tub. Added the stabilizer, waited 3 hours, jumped in and basically had a wild reaction to the water. I tested the water and the pH has plummeted to 7.2 and there is no measurable chlorine FC or TC. Adding the cya was a huge mistake. One dealer had no idea what cya was and said try it, the other dealer said don't do it. We did, *sigh*.

So, we are going to dump the water on the weekend and start over. The sad thing though is that we don't even know what starting over is anymore. Our dealer tells us one thing, we read another, honestly, kudos to all of you who can get it right.

Oh yeah. being a salt water tub just seems to make it even harder to deal with. Are there any Arctic Spa owners out there, with a chlorine system that can shed any light on our plight?

Thanks for Listening...Tom

Hey Tom,

Stabilizer is not necessary in a spa, as Cyanuric Acid is to keep sun light (UV light) from breaking down the free chlorine in the spa. As a spa is covered much of the time it is not needed. Cya creates other issues in such a small bather load as well.

Feel free to contact me and I will be happy to help you work this issue out.

Kind regards,

James

Hey James,

Yeah, we need help. I'll call later today.

Thanks for the Offer...Tom

[quantumchromodynamics]

Hey Tom,

Stabilizer is not necessary in a spa, as Cyanuric Acid is to keep sun light (UV light) from breaking down the free chlorine in the spa. As a spa is covered much of the time it is not needed. Cya creates other issues in such a small bather load as well.

Feel free to contact me and I will be happy to help you work this issue out.

Kind regards,

James

James, cyanuric acid is not just to protect chlorine from sunlight.

It also helps hold some chlorine in reserve to be released as needed. That way all of the chlorine is not active at the same time. It helps reduce excessive oxidation from the excess chlorine people use to ensure chlorine availability as some gets used up.

I would like to know what "other issues" you think cyanuric acid will cause.

[quantumchromodynamics]

Tom, it's important to know the effects of adding certain chemicals. The poolcalculator has a section called

"Effects of adding chemicals".

It shows that the pH drop is about what you would expect from adding the cyanuric acid. It would have been better to add cyanuric acid by using dichlor until your cyanuric acid reached the correct level.

Can you describe the rash in detail? Where, color etc?

[quantumchromodynamics]

Tom, I recommend that you try Nitro's guide to water maintenance. On fill up, leave out the salt and leave the salt cell off.

Also, what test kit do you have?

It is critical that you get a good test kit, such as the Taylor K-2006.

[TomC]

Tom, I recommend that you try Nitro's guide to water maintenance. On fill up, leave out the salt and leave the salt cell off.

Also, what test kit do you have?

It is critical that you get a good test kit, such as the Taylor K-2006.

Hi Quant,

We bit the bullet and emptied and refilled the tub. We really did wrestle with leaving the generator off and just working with tablets. In the end though, we figured we would give the generator one more go. This will be our first fill with the Taylor K-2006 kit and hopefully we can stay on top of the chemistry. I am really hoping that the rash was the result of pH of 8.2 (that is what it was reading when we moved away from the test strips). With the Taylor kit, we will keep it in the 7.4 - 7.6 range.

The rash is raised, red, and itchy. It is on my back and both sides of my abdomen. There are some spots on my legs and arms but they are not as concentrated as my back and abdomen. Oh yeah, the itchiest areas are very dry. I have had it for weeks now. My doc is trying to get me into a dermatologist but no luck so far. The itch seems to be diminishing but slowly. I am a scrather so it is not a pretty sight.

Cheerio...Tom

[chem geek]

Tom,

Can you look at the table in this link and determine if it seems that your rash is caused by a chemical reaction vs. a bacterial infection?

Richard

[bart6453]

Tom, I recommend that you try Nitro's guide to water maintenance. On fill up, leave out the salt and leave the salt cell off.

Also, what test kit do you have?

It is critical that you get a good test kit, such as the Taylor K-2006.

Hi Quant,

We bit the bullet and emptied and refilled the tub. We really did wrestle with leaving the generator off and just working with tablets. In the end though, we figured we would give the generator one more go. This will be our first fill with the Taylor K-2006 kit and hopefully we can stay on top of the chemistry. I am really hoping that the rash was the result of pH of 8.2 (that is what it was reading when we moved away from the test strips). With the Taylor kit, we will keep it in the 7.4 - 7.6 range.

The rash is raised, red, and itchy. It is on my back and both sides of my abdomen. There are some spots on my legs and arms but they are not as concentrated as my back and abdomen. Oh yeah, the itchiest areas are very dry. I have had it for weeks now. My doc is trying to get me into a dermatologist but no luck so far. The itch seems to be diminishing but slowly. I am a scrather so it is not a pretty sight.

Cheerio...Tom

Tom...you need to slow things down a bit.

You are jumping in a tub way too soon after adding god knows what and basically hoping for the best.

Re-fill your tub, listen to Nitro's advice on water maintenance, get you water BALANCED, Keep it that way for a few days....and really understand what is going on with your water.

Then, and only then, get in your tub.

If the thought of water balance issues is swimming around in your head...don't jump in. It is just going to exacerbate your water and skin problems.

You have taken the first great steps firstly by reading on this board to educate yourself about your water, and secondly by getting yourself a proper test kit.

Good luck, you will get this all figured out.

[Mikey_in_NY]

Are you sure you're not allergic to salt water? I only ask this because when my son was younger he'd break out in a rash after swimming in the ocean, but would never have this problem in a chlorine pool or hot tub. He's since grown out of this problem.

Can you run your tub on chlorine only, or does your setup mean you have to use salt?

[quantumchromodynamics]

Tom, I think that seeing a dermatologist is a good idea. There are several medical conditions that could cause what you describe. Some are exacerbated by heat.

I think that testing for free chlorine and combined chlorine with your FAS DPD test kit will help you rule out a bacterium, such as Pseudomonas aeruginosa. Maintain a consistent 1 to 4 ppm of free chlorine and maintain a 0.0 combined chlorine.

If you get some cyanuric acid in the water, maintain a 2 to 5 ppm chlorine level.

If the free chlorine goes below 1.0, or there are any chloramines, it is important to shock to about 10 ppm. Don't reenter the water until all of the combined chlorine is gone and the free chlorine is 5.0 ppm or less.

Do you think that the rash could be fiberglass? Sometimes fiberglass tubs or components lose their gel coats and the fiberglass can cause an itchy rash similar to what you describe.

[TomC]

Tom, I think that seeing a dermatologist is a good idea. There are several medical conditions that could cause what you describe. Some are exacerbated by heat.

I think that testing for free chlorine and combined chlorine with your FAS DPD test kit will help you rule out a bacterium, such as Pseudomonas aeruginosa. Maintain a consistent 1 to 4 ppm of free chlorine and maintain a 0.0 combined chlorine.

If you get some cyanuric acid in the water, maintain a 2 to 5 ppm chlorine level.

If the free chlorine goes below 1.0, or there are any chloramines, it is important to shock to about 10 ppm. Don't reenter the water until all of the combined chlorine is gone and the free chlorine is 5.0 ppm or less.

Do you think that the rash could be fiberglass? Sometimes fiberglass tubs or components lose their gel coats and the fiberglass can cause an itchy rash similar to what you describe.

Hi All,

I don't think it is a fibreglass issue - but honestly I am not certain about anything at the moment. We have dumped the water and refilled. This time I will make sure that I don't get in the tub if the pH is above 7.8. For those of you following, I am systematically eliminating potential compounds. So far we have stopped using MSP, and now we are looking at verifying that it is not a pH issue. That being the case, we are working diligently at keeping the pH down (not an easy task we are learning).

If it is not the pH then we may try bromine or switch off the salt generator and use diclor.

Thanks...Have a Great Weekend...Tom

[quantumchromodynamics]

I think that you would do best with a pH of about 7.5. Hypochlorous acid is a weak acid with a pKa of about 7.5. That means that it is half hypochlorous acid and half hypochlorite ion at a pH of 7.5.

As the pH increases, the percentage of hypochlorous acid decreases and the percentage of hypochlorite ion increases. Hypochlorous acid is the effective sanitizer. Hypochlorite ions are not good sanitizers.

pH.........Hypochlorous acid........Hypochlorite ion

7.4.................56 %..............................44 %

7.5.................50 %..............................50 %

7.6.................44 %................ .............56 %

7.7................ 39 %..............................61 %

7.8.................33 %..............................67 %

7.9.................28 %..............................72 %

8.0.................24 %..............................76 %

8.1.................20 %..............................80 %

8.2.................17 %..............................83 %

8.3.................14 %..............................86 %

8.4.................11 %..............................89 %

8.5.................09 %..............................91 %

[chem geek]

As shown in the graphs in this post, the drop in active chlorine (hypochlorous acid) with rising pH isn't as great when there is Cyanuric Acid (CYA) in the water as it tends to buffer hypochlorous acid. So I wouldn't worry too much about that. Also, it is unusual for a pH of even 8.0 to be irritating though clearly you can try something closer to 7.5 to see if it makes any difference. The typical pH of human tears is near 7.5 which is the main reason for that target. Tap water, however, is often from 7.7 to 8.2.