Low Combined Chlorine = Good?

[Gibson00]

Been a couple days since changing my water.  Using dichlor granuals for this first week at least.  I initially brought the chlorine to about 7ppm.  When I went to soak about 30 hours later I think, it had gone down to 2, and I've just been adding 1-2 teaspoons each day to take it back up to about 4 or 5.  Everything seems OK so far.
This morning I did the same, went for a soak, added the chlorine after.  Let it mix for a while and then decided to test it with the taylor kit.  Free chlorine measured around 4 or just over (should I raise it to more like 7 between soaks?).  But then for the first time, I decided to go further and measure the combined chlorine.
I added the 5 drops to my used sample water, and it barely turned pink at all.  And then probably took 2 - 3 drops to turn perfectly clear, so something like .6 ppm of combined.

Am I right in assuming that is a good thing?  Means my chlorine isn't all being used up?  I'm thinking this would make sense since I'm the only one who has used the spa over the past couple days, and probably for no more than 30 minutes a day.

Thanks!

[Vinny]

To answer your question - yes, it's good. But it is at the point where you should consider burning it off so it doesn't climb higher and start to have that chlorine smell. To do that you need 10 x that value ( it seems you do get that so maybe a tad more chlorine to help it along) or use non chlorine shock. If you use the non chlorine then run the tub for 20 minutes with all the jets on. The kit will show as a loit of combined chlorine if you test for a few days.

You may want to consider lowering the amount of chlorine you're using. The idea is to have 3 ppm chlorine 20 minutes after putting it in. More is OK, less is not. It is possible to be soaking in close to zero  chlorine. This is just a suggestion, feeling safe while soaking is the important thing.

[Gibson00]

Thanks Vinny.
On this new fill, I was kind of shying away from the non-chlorine shock as I hate having to leave the tub open and running for another 20 minutes after I'm done, always seem to be rushing out with the kids, etc, also hate leaving it open longer than necessary in the cold weather! 

One other question (sorry!) - If I am going to try to switch to bleach shortly, is it necessary to add borates, or is that optional?  If I understand correctly, it makes it a little easier to control the PH when using bleach?  Just a little shy to add borates with young kids using the spa often and inevitably like to dunk their heads a bit, etc..

[Vinny]

I have been using bleach for years in both my pool and spa and I missed the whole borate discussion. I know chem geek says to use it but honestly I don't although I do use borax at times to adjust pH. I have the pleasure of being able to use baking soda and it raises both my alkalinity and pH to the correct levels and they stay there for a while.

My suggestion is to try it without and see how your pH does. You will have to adjust pH every so often anyway with whatever you use, it is not something that stays rock solid forever. If you find you need to fiddle with pH every couple of days then it may be time to use borates, if you can go a week or two then I say use your judgement. Adding a little baking soda or borax to raise the pH every so often is not that big a deal IMO.

One last thing, whether you shock with chlorine or not you should leave your cover open for a while. I usually leave my cover open about 5 minutes for a regular dose and 20 minutes for shock.

Hopefully, it doesn't sound like a massive project ... it does get easier as you do it for a while!

[chem geek]

One of the reasons I suggest using 50 ppm Borates as an additional pH buffer when the TA is kept low (usually at around 50 ppm) to slow down the rate of pH rise when using hypochlorite sources of chlorine is due to this post on another forum.  Below my quote the person wrote the following:

I was warned by many people through emails that you won't listen to facts. The term google king was used and I understand their frustration. Anyone can claim to be anything online these days and google any term they want. That explains someone who doesn't own a spa or work with them hanging out on a spa forum telling people how to care for them. It's a shame that you are misleading and hurting so many people. I've been helping them privately since they are afraid to speak out against you in the forum. Remember that I was brought here by a customer who followed your bleach advice. You don't listen to facts and you aren't interested in the truth. You do not have one shred of evidence to prove that dichlor is a problem in spas, period. And even if it were, bleach would not be the solution. If you need to believe the sky is red despite the truth that it's blue then keep on believing. I have over 20 years experience in the business and you don't even own a spa. It's absurd. If you don't have an agenda why don't you lead people towards bromine or other alternatives to dichlor? I helped my customer that was harmed by your advice and hopefully a few others here. One email stated that you think you own this forum. You clearly don't like your territory invaded by someone who has more knowledge than you which is understandable. Since I don't have any shortcomings in my life that send me to the internet looking for adoration, I will leave you to your little corner of the world.

The customer in question did not pay attention to her pH levels and they went too high and caused calcium carbonate scaling in her spa (in her case she had high CH and she may not have lowered TA as instructed but used bleach).  I don't want that situation to happen again so people should be cautioned that when they use bleach they need to make sure their pH doesn't rise too quickly and if it does take steps to mitigate that.  Lowering the TA reduces carbon dioxide outgassing but it also reduces pH buffering so having a supplemental pH buffer like the borates makes sense.  If you know what you are doing, then you don't have to use the borates, but after getting blasted by that dealer, I didn't want to take any chances.

Note that this dealer in this post is adamant that bleach (sodium hypochlorite) causes a pH rise in your water (not just upon addition, which it does, but over time even accounting for chlorine acidic usage/consumption, which it doesn't) so by believing that, there's no way one could think about lowering the TA level as a way of mitigating the pH rise -- it's so counter-intuitive.  He also states that sodium hypochlorite quickly becomes an inert substance at higher temperatures (not understanding that it's only when not using CYA that the chlorine will outgas faster -- it has nothing to do with the source of chlorine being hypochlorite -- I never said to use bleach alone, but always with CYA in the water most easily added by using Dichlor initially).  Any problems are attributed to how the science I describe must be wrong and what the industry writes in Pool & Spa News must be right.

[Vinny]

OK, it's pH rise that's a problem not lowering - so it finally hit my brain!  Although I have used bleach in my tub I haven't consistently so maybe that's why I haven't noticed it (along with I'm looking for it to fall LOL!)

Is there a reason to keep alkalinity at around 50? I usually shoot for around 80 or so but honestly I haven't tested for it in years due to the fact of my pH and alkalinity usually fall in line. I have to keep an eye on my pH a little closer since I am using bleach fairly regularly as of this water fill; it's hovering at 7.8 (a little high) and I'll take notice if it rises. I am due to add non chlorine shock which is acidic and I'll see if it does anything pH wise when I do add it.

chem geek, as I said in another post I do remember when you first arrived at this site and didn't get such a warm reception. I was familiar with the BBB method from my pool and used 2 of the Bs for my spa ...I left out the bleach. As I also said in that post, you came here with another person that had a more "in your face" style than you have ... I don't think that helped here! Glad your still around helping people understand this stuff!!!

One of the reasons I suggest using 50 ppm Borates as an additional pH buffer when the TA is kept low (usually at around 50 ppm) to slow down the rate of pH rise when using hypochlorite sources of chlorine is due to this post on another forum.  Below my quote the person wrote the following:

I was warned by many people through emails that you won't listen to facts. The term google king was used and I understand their frustration. Anyone can claim to be anything online these days and google any term they want. That explains someone who doesn't own a spa or work with them hanging out on a spa forum telling people how to care for them. It's a shame that you are misleading and hurting so many people. I've been helping them privately since they are afraid to speak out against you in the forum. Remember that I was brought here by a customer who followed your bleach advice. You don't listen to facts and you aren't interested in the truth. You do not have one shred of evidence to prove that dichlor is a problem in spas, period. And even if it were, bleach would not be the solution. If you need to believe the sky is red despite the truth that it's blue then keep on believing. I have over 20 years experience in the business and you don't even own a spa. It's absurd. If you don't have an agenda why don't you lead people towards bromine or other alternatives to dichlor? I helped my customer that was harmed by your advice and hopefully a few others here. One email stated that you think you own this forum. You clearly don't like your territory invaded by someone who has more knowledge than you which is understandable. Since I don't have any shortcomings in my life that send me to the internet looking for adoration, I will leave you to your little corner of the world.

The customer in question did not pay attention to her pH levels and they went too high and caused calcium carbonate scaling in her spa (in her case she had high CH and she may not have lowered TA as instructed but used bleach).  I don't want that situation to happen again so people should be cautioned that when they use bleach they need to make sure their pH doesn't rise too quickly and if it does take steps to mitigate that.  Lowering the TA reduces carbon dioxide outgassing but it also reduces pH buffering so having a supplemental pH buffer like the borates makes sense.  If you know what you are doing, then you don't have to use the borates, but after getting blasted by that dealer, I didn't want to take any chances.

Note that this dealer in this post is adamant that bleach (sodium hypochlorite) causes a pH rise in your water (not just upon addition, which it does, but over time even accounting for chlorine acidic usage/consumption, which it doesn't) so by believing that, there's no way one could think about lowering the TA level as a way of mitigating the pH rise -- it's so counter-intuitive.  He also states that sodium hypochlorite quickly becomes an inert substance at higher temperatures (not understanding that it's only when not using CYA that the chlorine will outgas faster -- it has nothing to do with the source of chlorine being hypochlorite -- I never said to use bleach alone, but always with CYA in the water most easily added by using Dichlor initially).  Any problems are attributed to how the science I describe must be wrong and what the industry writes in Pool & Spa News must be right.

[chem geek]

If you don't use any net acidic chemicals and are using bleach, then unless your TA was lower you'd likely experience the pH rising.  You might have lower aeration (less use of spa jets) in your spa than most.  Or you use net acidic chemicals on occasion whether that be Dichlor, MPS, or something else.

After switching from Dichlor which is net acidic to bleach which is mostly neutral (I'm referring to the NET effect after chlorine usage/consumption that is acidic), most people experience the pH rising in their spa.  By lowering the TA level that slows down carbon dioxide outgassing that is the source of that pH rise because the water is over-carbonated.  One also targets a higher pH of around 7.7 to 7.8 or thereabouts.  However, if the pH still rises then using 50 ppm Borates will slow that down.  Though one may still need to add acid, one doesn't need to add it as frequently when borates are being used.

[Gibson00]

My my pH seems to always be a bit on the high side to begin with...

For those that just use dichlor, and don't switch to bleach, I'm assuming the issue there is high cya?  And the solution to that is basically dilution?  Are folks using dichlor really changing out their water often enough to dilute cya?

If one does go with borates, is there a rough guide of how much to add to a 500 gallon tub to get to 50ppm?

Thanks

[Quickbeam]

My my pH seems to always be a bit on the high side to begin with...

For those that just use dichlor, and don't switch to bleach, I'm assuming the issue there is high cya?  And the solution to that is basically dilution?  Are folks using dichlor really changing out their water often enough to dilute cya?

If one does go with borates, is there a rough guide of how much to add to a 500 gallon tub to get to 50ppm?

Thanks

Sorry, can't help you with the dichlor, bleach question, but for the borates, you can use the pool math calculator, which can be found here: http://www.troublefreepool.com/calc.html

[sksmoker]

i wouldn't worry much about CYA at this point. You just got your test kit and are figuring everything out along the way. My water runs from Nov-Mar so my CYA should be sky high by the end but it is about 110 or so at the end. Remember, if you are still using your trichlor pucks they are net acidic and full of CYA, so switch to bleach and you should be ok.

I would also shy away from adding 50ppm borates. Your mini pucks will take care of the ph over time and will slowly keep lower it. If your ph keeps creeping up then address it using a bit of ph minus(down) and it should settle into a pattern.

Put your chemicals in and close the tub. There is a lot of "should" here but from what I found out for what people _really_ do vs what they _should_ do, are quite different

You might wear out the underside of your cover a bit quicker but hey, when it's -25C outside, no one wants to keep the lid open, or go back out to close it!

After a year, I haven't noticed any noticeable effects to the underside of my lid.

How is the coughing/aggravated lung issue after the water change and dichlor?

[Gibson00]

Sorry Sksmoker, missed your reply.

So I refilled the tub a little over a week ago, had to anyway to re-attach a couple of intake covers that had come loose.
Since starting fresh, I have not used any of the trichlor tabs.  It was keeping my chlorine levels at about 14ppm according to the Taylor kit.
So I decided to do the dchlor to bleach method.  I used dichlor for about a week to keep the chlorine up around 5ppm after a soak, and it would usually fall to about 2ppm for the next day.  Then I switched to bleach, I think about 6% (Clorox original, or something like that).  Seems like about 50ml's of it raises the chlorine level by roughly 2ppm....not sure if that makes sense or not.  I'm still using Aquafinesse simply because I have some, but will probably stop after I run out due to the expense of it.  And I used a couple capfulls (about 50g) of non-chlorine shock at the end of the first week.
So far things seem to be going well.  The steam doesn't seem to be making me cough nearly as much as before or at all.  I'm thinking that bathing in 14ppm chlorine might have been part of the issue!!