Cyanuric Acid

[Spahead007]

Hello Fellow Spaheads,

Newbie here, bought a 7x7 Artic Spa last August and using chlorine and have been having some water balance issues.I have read some of the posts here and have made some things clear,however

my cyanuric level is about 100 I know this is bad and because it is that high I will probably have to drain and start over. Can anyone out there tell me how the cyanuric acid levels increase,what causes this to happen?

Thank You in Advance

[poolyeti]

spahead,

CYA is added into your spa every time you use dichlor to sanitize your spa. The only way to lower the CYA levels is to lose water. I recommend using a bromine disifection system and not having any CYA at all in your spa

[waterbear]

Hello Fellow Spaheads,

Newbie here, bought a 7x7 Artic Spa last August and using chlorine and have been having some water balance issues.I have read some of the posts here and have made some things clear,however

my cyanuric level is about 100 I know this is bad and because it is that high I will probably have to drain and start over. Can anyone out there tell me how the cyanuric acid levels increase,what causes this to happen?

Thank You in Advance

There are two types of chlorine, stabilized and unstabilzied. Stabilized chlorine are chemicals made from chlorine and cyanuric acid, chlorinated isocynaurates. Dichlor, which is the most common form of chlorine used in spas, is a chlorinated isocyanurate. The other is trichlor but that is not really used in spas because it has such a low pH. For each 1 ppm of free chlorine dichlor adds it is adding .9 ppm of CYA! Since chlorine gets consumed and CYA does not the level of it can build up very fast.

Unstabilized chlorine does not contain CYA. There are three unstabilized chlorines--sodium hypochlorite (often called liquid chlorine) or bleach (same thing!), lithium hypochlorite, and calcium hypochloite. The last two are granular and all three are marketed for use in spas as a sanitizer and/or shock. Lithium hypochlorite is fast dissolving but very expensive. Calcium hypochlorite is slow dissolving and will cause calcium hardness to increase, not an issue if you are doing regular water changes as long as you watch your pH and don't have very hard water to begin with. They are all pretty much interchangable. Chlorine is chlorine once it's in the water!!!!!!!!!!!!!! Only difference is if they are adding CYA or not.

There is some evidence that having a CYA level of around 20 ppm is optimal for a spa but at least one state has outlawed the use of CYA or stabilzied chlorine in spas completely and most others limit the permitted level in commercial spas. Too high CYA level will inhibit chlorines sanitizing ability and permit such nasties as psuedomonas to grow (causes hot tub itch).

[dilauro]

Recently Ive been dealing with Hot Tub Rash...

From the different threads on this forum and other forums, there seems to be a relationship about the CYA

levels.

1) Say that 20ppm is a good level

2) Too much can make it difficult to maintain a good Free Cholrine level which in turn can lead to bacteria growing,= Itch

3) Test strips can not test for CYA levels

4) Two local Spa Service reps told me to ignore CYA, just make sure the Free Cholrine level is between 3 and 5

5) Drain, dont drain the spa, run the Filter more instead.

Comments welcomed, I can tell you reading more documents, listening to more people , reading different forums, can just

make this more confusing.

[waterbear]

Recently Ive been dealing with Hot Tub Rash...

From the different threads on this forum and other forums, there seems to be a relationship about the CYA

levels.

1) Say that 20ppm is a good level

I would agree with that. If the spa is exposed to sunlight and not covered higher might even be better

2) Too much can make it difficult to maintain a good Free Cholrine level which in turn can lead to bacteria growing,= Itch

No, to to maintain a proper ACTIVE FC level you need to increase your FC as your CYA increases. FC combines with CYA to form chlorinated isocynaurates. The higher the CYA the higher the FC needs to be to allow enough excess FC that does not combine and stays acitve in your water. While chlorinated isocyanurates are santizers they are not nearly as active as FC (hypchlorous acid).

3) Test strips can not test for CYA levels

They can, they just don't do it accurately!!!!!!!!!

4) Two local Spa Service reps told me to ignore CYA, just make sure the Free Cholrine level is between 3 and 5

Pretty much standard rhetoric. They will also tell you to slug acid to lower TA and to dilute it to lower pH...another fallicy and this one has been debunked for years now! (Doesn't matter which way you do it, efffect on TA and PH will be the SAME for a give amount of acid added!)

5) Drain, dont drain the spa, run the Filter more instead.

Draining and refilling WILL lower the CYA. Filtering more will have no effect on it. If you have pseudomonas growing in the tub you want to drain, refill, and sterilize it by raising the FC to abut 20-30 ppm with an unstabilzed chlorine souce such as cal hypo or (gasp!) liquid chlorine or bleach.

Comments welcomed, I can tell you reading more documents, listening to more people , reading different forums, can just

make this more confusing.

Hope this helps. And if anyone wants to question my advice I do happen to work in the industry! (reference to the recent attack by a 'professional' against one of the active members here who gave, IMHO, EXCELLENT advise and who has stopped posting here as a result! Said 'professional' has since disappeared from the board! Kind of says it all, don't it!)

You might also want to read this thread!

[dilauro]

Recently Ive been dealing with Hot Tub Rash...

From the different threads on this forum and other forums, there seems to be a relationship about the CYA

levels.

1) Say that 20ppm is a good level

I would agree with that. If the spa is exposed to sunlight and not covered higher might even be better

2) Too much can make it difficult to maintain a good Free Cholrine level which in turn can lead to bacteria growing,= Itch

No, to to maintain a proper ACTIVE FC level you need to increase your FC as your CYA increases. FC combines with CYA to form chlorinated isocynaurates. The higher the CYA the higher the FC needs to be to allow enough excess FC that does not combine and stays acitve in your water. While chlorinated isocyanurates are santizers they are not nearly as active as FC (hypchlorous acid).

3) Test strips can not test for CYA levels

They can, they just don't do it accurately!!!!!!!!!

4) Two local Spa Service reps told me to ignore CYA, just make sure the Free Cholrine level is between 3 and 5

Pretty much standard rhetoric. They will also tell you to slug acid to lower TA and to dilute it to lower pH...another fallicy and this one has been debunked for years now! (Doesn't matter which way you do it, efffect on TA and PH will be the SAME for a give amount of acid added!)

5) Drain, dont drain the spa, run the Filter more instead.

Draining and refilling WILL lower the CYA. Filtering more will have no effect on it. If you have pseudomonas growing in the tub you want to drain, refill, and sterilize it by raising the FC to abut 20-30 ppm with an unstabilzed chlorine souce such as cal hypo or (gasp!) liquid chlorine or bleach.

Comments welcomed, I can tell you reading more documents, listening to more people , reading different forums, can just

make this more confusing.

Hope this helps. And if anyone wants to question my advice I do happen to work in the industry! (reference to the recent attack by a 'professional' against one of the active members here who gave, IMHO, EXCELLENT advise and who has stopped posting here as a result! Said 'professional' has since disappeared from the board! Kind of says it all, don't it!)

You might also want to read this thread!

Thanks, I appreciate your response and the details.

[sandi]

When we got our spa, we used dichlor exclusively at the advice of a friend. By the time I learned about dichlor raising CYA levels, ours was already very high and I have not wanted to drain and refill the spa b/c of the cold weather. Did remove about 50 gallons and refilled with fresh water on 2 different occasions, about a month apart, and have switched to using bleach. Neither my husband nor I have had any problem with hot tub itch, despite the high CYA level. Does this mean the bacteria isn't in the water or have we just been lucky? Or are some people more susceptible (sp?) to the bacteria than others? If CYA is high, does it mean that pseudowhatevers are in the water? Our water looks and smells OK and I'm thinking that, in another couple of weeks, we'll do a water change. Thanks.

Sandi

[Hillbilly Hot Tub]

When we got our spa, we used dichlor exclusively at the advice of a friend. By the time I learned about dichlor raising CYA levels, ours was already very high and I have not wanted to drain and refill the spa b/c of the cold weather. Did remove about 50 gallons and refilled with fresh water on 2 different occasions, about a month apart, and have switched to using bleach. Neither my husband nor I have had any problem with hot tub itch, despite the high CYA level. Does this mean the bacteria isn't in the water or have we just been lucky? Or are some people more susceptible (sp?) to the bacteria than others? If CYA is high, does it mean that pseudowhatevers are in the water? Our water looks and smells OK and I'm thinking that, in another couple of weeks, we'll do a water change. Thanks.

Sandi

CYA is not a bacteria. It is an acid that helps prevent chlorine loss is open bodies of water. Some people are sensitive to it. It does not mean you have any "bugs" in your water. Each time you add dichlor to the tub you are adding CYA. It starts getting very high and it does not go away. The only way to get rid of it is drain the tub. Do your water changes when you are suppose to to prevent anything from getting bad and if you use chlorine, make sure to follow chem geeks FULL explanation/treatment to prevent other issues.

[sandi]

CYA is not a bacteria. It is an acid that helps prevent chlorine loss is open bodies of water. Some people are sensitive to it. It does not mean you have any "bugs" in your water. Each time you add dichlor to the tub you are adding CYA. It starts getting very high and it does not go away. The only way to get rid of it is drain the tub. Do your water changes when you are suppose to to prevent anything from getting bad and if you use chlorine, make sure to follow chem geeks FULL explanation/treatment to prevent other issues.

I guess I didn't make myself clear in my previous post - I know what CYA is and what it isn't. On 2/28 in this thread, someone stated that he is having trouble with hot tub itch and alluded to the fact that it is because pseudomonas are more likely to be growing in the water since the high CYA level is minimizing the effectiveness of the chlorine. I know that our CYA level is high due to using dichlor exclusively when we first got the spa yet we have had no problems with hot tub itch. I'm just wondering if there is a direct correlation between high CYA levels and pseudomonas?

Put another way, can a spa have a high level of CYA and still have clean, bacteria-free water?

Sandi

[waterbear]

I'm just wondering if there is a direct correlation between high CYA levels and pseudomonas?

High cyanuric acid levels will decrease the sanitizing ability of chlorine and make it easier for microorganisms to grow in the water. High levels of cyanuric acid do not mean they WILL grow but that they are much more likely to grow since they won't be killed as quickly.

Put another way, can a spa have a high level of CYA and still have clean, bacteria-free water?

Sandi

Bacteria free?, probably not. Clean?, well that depends on what you mean by "clean". Will pseudomonas grow? Most likely if it gets introduced into the tub. If it is never introduced into the water it obviously will not grow there. However, be aware that it is a fairly common microorganism and is usually introduced into hot tubs via swimsuits. High CYA does not mean that you WILL get hot tub itch, it just means that your water is probably not sanitized as well as it should be and the possiblity that you will get hot tub itch or another water borne illness is much greater. Psuedomonas is also repsonsible for what has been called 'hot tub lungs' or 'hot tub cough'.

[TinyBubbles]

When we got our spa, we used dichlor exclusively at the advice of a friend. By the time I learned about dichlor raising CYA levels, ours was already very high and I have not wanted to drain and refill the spa b/c of the cold weather. Did remove about 50 gallons and refilled with fresh water on 2 different occasions, about a month apart, and have switched to using bleach. Neither my husband nor I have had any problem with hot tub itch, despite the high CYA level. Does this mean the bacteria isn't in the water or have we just been lucky? Or are some people more susceptible (sp?) to the bacteria than others? If CYA is high, does it mean that pseudowhatevers are in the water? Our water looks and smells OK and I'm thinking that, in another couple of weeks, we'll do a water change. Thanks.

Sandi

Sure you can Sandi. Here is info. from the mayo clinic on the two different bacteria that cause hot tub itch and hot tub lung.

Here is the link for pseudomonas http://www.mayoclinic.com/health/folliculi...0512/DSECTION=2

You notice it mentions that keeping your chlorine levels and ph levels in the correct range is important, with no mention of cya.

Here is the link for hot tub lung http://www.mayoclinic.com/health/hot-tub-lung/AN00660

Again, the reference the CDC's guidelines for proper disinfectant levels and ph levels in a hot tub, again with no mention of cya.

The Mayo Clinic and CDC are as high up as you can get on the health field ladder. I feel safe in my spa following their guidelines and suggestions.

[104 Degrees]

Bacteria free?, probably not. Clean?, well that depends on what you mean by "clean". Will pseudomonas grow? Most likely if it gets introduced into the tub.

Waterbear

Do you think i could keep my CYA down and use dichlor(only) if i drain & Refill a Quarter of the tub Starting the second month and doing it the third month also??. I do belive in dumping the tub at the end of three months.Sorry to hear about Richard.

[waterbear]

The Mayo Clinic and CDC are as high up as you can get on the health field ladder. I feel safe in my spa following their guidelines and suggestions.

Their guidlines are based on the EPA recommendations. The EPA is the governing body concering sanitizers for recreational water in the US. Only very recently has the EPA changed it's stance about CYA and has merely said that levels of FC should be higher when CYA is present but have offered no other guidlines. Like I stated before the stance that is commonly posted is based on the Pinellas County Study from the 80s which was funded by a manufacturer of stabilized chlorine. It is interesting that just a few years ago silver and coppper/silver system were permitted be sold as 'chlorine free' in this country but that situation has changed in only the past 2 years! Now they are requried to be used with chlorine (or bromine) and most manufactuers get around saying just how much is really needed by saying that the water needs to be shocked on an as needed basis so if they are shocking every 2 days in their tests the water stays sanitized! Many medical authorities still say that copper and silver are effective treatments for spas and pools without chlorine even though the hard evidence has shown otherwise! Dr. Andrew Weil touts metal ion systems as a chemical free and chlorine free method of spa and pool sanitiztion, however, his expertise is NOT in water sanitation but rather in alternative medicine. Hardly an expert opinion if you ask me.

Hopefully you never have problems in your tub from overstabilzation but be aware that is it very real and it does happen. I have seen it first hand on more than one occasion! You have experience with one hot tub. I have experience with many. If overstabilization was not real would ARCH Chemical have info on their website about overstabilization? Funnily enough Chemtura, who manufacuters most of the stabilzied chlorine out there, says that overstabilzation does not exist. Hmmm, if it did it might be bad for their business!

[wireman]

So Tiny, just because Mayo and another place didn't mention CYA doesn't mean it isn't a factor. Did they mention jusing dichlor or just chlorine? I checked both those links you provided. Both were very sparse in anything resembling a hot tub maintenance routine. If you feel comfortable basing the use of dichlor and rising cya levels on the word of spa reps who can't balance a chemical equation to save their life and two mayo docs that barely mention chlorine then that's your choice. But telling eveyone else that cya is a non-issue because you have decided that it is based on a complete lack of science is suspect to me at best.

[TinyBubbles]

So Tiny, just because Mayo and another place didn't mention CYA doesn't mean it isn't a factor. Did they mention jusing dichlor or just chlorine? I checked both those links you provided. Both were very sparse in anything resembling a hot tub maintenance routine. If you feel comfortable basing the use of dichlor and rising cya levels on the word of spa reps who can't balance a chemical equation to save their life and two mayo docs that barely mention chlorine then that's your choice. But telling eveyone else that cya is a non-issue because you have decided that it is based on a complete lack of science is suspect to me at best.

[TinyBubbles]

So Tiny, just because Mayo and another place didn't mention CYA doesn't mean it isn't a factor. Did they mention jusing dichlor or just chlorine? I checked both those links you provided. Both were very sparse in anything resembling a hot tub maintenance routine. If you feel comfortable basing the use of dichlor and rising cya levels on the word of spa reps who can't balance a chemical equation to save their life and two mayo docs that barely mention chlorine then that's your choice. But telling eveyone else that cya is a non-issue because you have decided that it is based on a complete lack of science is suspect to me at best.

Wow, I wonder why you are so angry. I'd prefer you don't reply to my posts rather than hurl insults at people that you know nothing about. Do you personally know the spa reps that I know? Do you know that they can't balance a chemical equation to save their life? In fact, your post is the one with no science behind it.....only unkind insults.

[waterbear]

Tiny,

Let's look at the facts here....you had problems balancing your spa except when you were using dichlor so you needed to justify that dichlor was the only way to santize a spa. IF your spa has an ozonator you won't be able to maintain a FC residual if the ozone generates all the time (which many of the cheaper units do).You got your dealer to make a kamakazie visit and drive chemgeek away and then disappear and now you are the dichlor champion and try to defend you postition on very weak evidence. I will gladly take your dealer on one on one with the chemistry and I DO work in the industry!

Dichlor is NOT the only chlorine source for spas. Overstabililization is real. Most of the recommendations are still based on the flawed Pinellas County study but the effects of CYA were actually know before this. Do you think there is a reason that CYA lowers ORP readings (or am I over your head right now?)

IF you don't want anyone answering your posts I have an easy solution....just don't post!

I also noticed that you have been a memeber here since only last september yet you are averaging over 100 posts a month!!!!! Something to think about....perhaps you need a hobby!

[TinyBubbles]

Tiny,

Let's look at the facts here....you had problems balancing your spa except when you were using dichlor so you needed to justify that dichlor was the only way to santize a spa. IF your spa has an ozonator you won't be able to maintain a FC residual if the ozone generates all the time (which many of the cheaper units do).You got your dealer to make a kamakazie visit and drive chemgeek away and then disappear and now you are the dichlor champion and try to defend you postition on very weak evidence. I will gladly take your dealer on one on one with the chemistry and I DO work in the industry!

Dichlor is NOT the only chlorine source for spas. Overstabililization is real. Most of the recommendations are still based on the flawed Pinellas County study but the effects of CYA were actually know before this. Do you think there is a reason that CYA lowers ORP readings (or am I over your head right now?)

IF you don't want anyone answering your posts I have an easy solution....just don't post!

I also noticed that you have been a memeber here since only last september yet you are averaging over 100 posts a month!!!!! Something to think about....perhaps you need a hobby!

Fact 1: My dealer has never been on this forum. My dealer has no idea that I ever put bleach in my spa and I plan to keep it that way. Do you suggest I call him up and give him information that will void my warranty?

Fact 2: I don't respond to bullies nor do I run from them. I will post on this forum how every many times I choose. After this post, however, I will not respond to your childish lies or insults.

Fact 3: If chemgeek chose to take his ball and go home, that's his decision. That has nothing to do with me. Grow up.

Question 1: How many times a month have you posted on this and many other forums? Do you need a hobby? Maybe we could find one together.

Question 2: If I am the champion of dichlor does that make you the champion dichlor basher? Wouldn't that be the pot calling the kettle black?

Question 3: Am I over your head right now if I work for a pool company that has been in business for 26 years and does 5 million a year in business? Have you tested enough water to gross 5 mil a year? We design and build internationally award winning pools. While we don't sell chemicals or portable spas, I have access to numerous cpo's (is that over your head?), nspi trained professionals and countless people in the pool & spa business.

Question 4: Could you please show me the quote where I stated that dichlor is the only way to sanitize a spa. Perhaps I'm sleep typing.

Question 5: Are you a hypocrit? Maybe I am wrong, but you being so upset that someone drove away chemgeek and then telling me not to post anymore sounds a tad hypocritical.

Finally, I do not mind if mature people respond to posts in regards to water chemistry, which is the name of this forum. I see no point in someone responding with immature name calling or insults. If that's what I'm looking for there is a daycare right next door.

[wireman]

I didn't mean to put any insults in my post. I'm betting that most hot tub dealers are not chemists and can't balance a chemical equation, that's not an insult but a speculation. And I'm not angry but just sorta amused that posts supporting dichlor and ignoring cya seem so conclusive. I honestly don't think it's a huge problem but to those that are really concerned that their water be the safest and best that it can be and are using chlorine I think that being aware of cya is reasonable. I haven't found any information showing that cya is a non-issue. I have found information showing that it is. I would like to see any information showing that sanitation does not decrease with increased cya use. Or even some federal or state agencies that have adopted the stance that cya is a non-issue. I do find a lot of states require pools to not be over 100ppm cya. This in itself says there is a reason for that.

[tony]

I didn't mean to put any insults in my post. I'm betting that most hot tub dealers are not chemists and can't balance a chemical equation, that's not an insult but a speculation. And I'm not angry but just sorta amused that posts supporting dichlor and ignoring cya seem so conclusive. I honestly don't think it's a huge problem but to those that are really concerned that their water be the safest and best that it can be and are using chlorine I think that being aware of cya is reasonable. I haven't found any information showing that cya is a non-issue. I have found information showing that it is. I would like to see any information showing that sanitation does not decrease with increased cya use. Or even some federal or state agencies that have adopted the stance that cya is a non-issue. I do find a lot of states require pools to not be over 100ppm cya. This in itself says there is a reason for that.

I am now entering my fourth month of experimenting with only bleach to sanitize my spa. Four months is my normal drain and fill time and I will comment on the results at that time. My water, though, seems exceptionally fresh for three month old water. I know that each ppm chlorine will add .8 ppm salt and the use of liquid chlorine will add another .8 ppm salt to the water. Stabilized chlorine adds CYA to water but CYA must also contribute to TDS. I wonder if anyone knows how much TDS that CYA adds to water? Also, what happens to MPS after it oxidizes contaminates? Does it add to TDS and how much?

[waterbear]

Question 1: How many times a month have you posted on this and many other forums? Do you need a hobby? Maybe we could find one together.

Much less then the 100 posts a month you make. My total posts don't even come close to 1 post a day! Yours are over 3. Do the math.

Question 2: If I am the champion of dichlor does that make you the champion dichlor basher? Wouldn't that be the pot calling the kettle black?

I have no problems stating that I am not a fan of stabilized chlorine in systems with cartridge filters (which include almost all spas!) because there is no dilution of the water and the CYA levels build up very quickly leading to overstabilization. I feel the same way about pools with cartridge filters and trichlor feeders...not a good combination, especially in areas with extened swim seasons. I do not believe that dichlor is suitable for a shock since if applied too often (the once a week shocking routine that is so common) it quickly leads to high CYA levels. Dichlor is an acceptabtle form of chlorine for sanitization when sand filters are used and the swim season is short. I believe in using the proper form of chlorine for the system at hand. Cal Hypo is a much better choice for most spas if the water hardness is not that high. In fact, Arch Chemical does market cal hypo specifically for spa use! Lithium hypochorite is also an acceptable form of chlorine that has none of the hardness increasing and slow dissolving drawback of cal hypo but it is very expensive. The other unstabilized chlorine is sodium hypochlorite. You might know it as liquid chlorine since you are in the biz but then you must also know that it is one and the same as bleach! As you can see I do say that dichlor is an acceptable way of chlorination under certain circumstances which does NOT make me a diclor basher. If I was I would say that dichlor was never to be used at all!

Question 3: Am I over your head right now if I work for a pool company that has been in business for 26 years and does 5 million a year in business? Have you tested enough water to gross 5 mil a year? We design and build internationally award winning pools. While we don't sell chemicals or portable spas, I have access to numerous cpo's (is that over your head?), nspi trained professionals and countless people in the pool & spa business.

Then you must CERTAINLY know about overstabilization and how CYA affects chlorine's santizing ability. They talk about it in the CPO handbook! (Then again the CPO handbook still recommends 'slugging' acid to lower TA yet that myth had been debunked years ago in the JSPSI Journal. I believe it was the Fall 1995 edition.) Why the discord then. You must also know how to maintain the pH in your spa but you seemed to be having quite a bit of trouble. I have said it before and I will say it again. Pool builders build pools but most don't know beans about water chemisty! There might be the rare builder who understands pool chemistry but it is not their area of expertise. Once the pool is built they want to turn it over as fast a possible, don't they?

Question 4: Could you please show me the quote where I stated that dichlor is the only way to sanitize a spa. Perhaps I'm sleep typing.

How about this quote:

"You've just found a forum where most of us use dichlor."

from this post.

Question 5: Are you a hypocrit? Maybe I am wrong, but you being so upset that someone drove away chemgeek and then telling me not to post anymore sounds a tad hypocritical.

No, I said that if you don't want people responding to your posts then don't post. If you post you will get responses. Reread what I wrote! Here is the direct quote that you have a few messages up in your reply to wireman:

"I'd prefer you don't reply to my posts"

Did I get it right? I believe I did.

Finally, I do not mind if mature people respond to posts in regards to water chemistry, which is the name of this forum. I see no point in someone responding with immature name calling or insults. If that's what I'm looking for there is a daycare right next door.

Thankfully you won't be answering this as you stated in your previous post!

"After this post, however, I will not respond to your childish lies or insults."

[TinyBubbles]

I didn't mean to put any insults in my post. I'm betting that most hot tub dealers are not chemists and can't balance a chemical equation, that's not an insult but a speculation. And I'm not angry but just sorta amused that posts supporting dichlor and ignoring cya seem so conclusive. I honestly don't think it's a huge problem but to those that are really concerned that their water be the safest and best that it can be and are using chlorine I think that being aware of cya is reasonable. I haven't found any information showing that cya is a non-issue. I have found information showing that it is. I would like to see any information showing that sanitation does not decrease with increased cya use. Or even some federal or state agencies that have adopted the stance that cya is a non-issue. I do find a lot of states require pools to not be over 100ppm cya. This in itself says there is a reason for that.

Thanks for clearing that up. Sorry if I saw insults were none were intended. Many of the people I deal with have become friends over the years, not just business acquaintances. I'm proud to know them on both levels, so was hurt when I thought it was an insult. Again, sorry. I will admit that "non-issue" could be too strong, but the whole "sky is falling" approach is way to drastic as well. Everything I've found does state that the effectiveness of chlorine does go down with high cya levels. Most tests involving chlorine are at .5 fc with 99.99% kill in under 30 seconds. This won't happen with high cya levels which is why spas are supposed to be maintained at 2-5 ppm fc. If I was using dichlor alone, there is no way I'd accept .5 fc. I do not believe that would be safe. I had proof of this when using bleach. Take any bias I have out of the bleach issue. For me, I could not maintain fc with bleach so I ended up with cloudy, smelly water. I'm sure if I used only dichlor and ran .5 fc I would end up with roughly the same situation. I haven't ran into any problems with dichlor if I keep my fc levels up and I don't expect to. The only other point that I'd make is that when getting info. from the cdc and epa it's important to remember they are dealing with public health. The majority of us would have our kitchens shut down if the health inspector came in. That's not to say we aren't clean. We prepare meals and make a plate of leftovers for whoever isn't home and they eat it later. We don't stick a thermometer in it to make sure it's at the correct temperature until they get home. We prepare food for friends and family without wearing gloves or hairnets, etc. Restaurants here can't serve eggs with runny yolks or beef cooked less than medium, but we do it in our homes all the time. When dealing with public health and liability, the stakes are a little higher and the rules a little stricter. No doubt there are states with guidelines for public swimming facilities regarding cya, there are many more with guidelines for TDS. Here, a public pool is shut down if the TDS are too high, but no parameters for cya. I can't remember the exact figures, I'd have to look, but bleach sends TDS through the roof. While someone might want to see me as a champion of dichlor, I'm actually just trying to champion common sense. One can't cause hysteria over cya while ignoring TDS. To be quite honest, I think bromine is the most logical sanitizer for spas. I don't use it because it makes me itch and my skin smells. Even though I don't use it, I think it's a great product.

[David66]

Hi,

Waterbear, I for one appreciate your opinions on this forum. And I like to study those of other people, too, so let's all just keep it civilized so as to not drive anyone off like the case with Richard.

This dichlor vs bleach debate just keeps going, doesn't it

Just a couple quick questions:

If dichlor causes CYA levels to rise which is not generally a good thing (the increased probability of hot tub itch or worse)

And

Bleach can lead to high TDS levels, and rising pH levels which constantly need to be monitored and lowered (somehow)..

And

I don't want to use bromine,

What's the best approach?

I've been using bleach on this fill, which was done the day after Christmas. So far, I've had nice, clear water, no itching or other issues. I got my Alk levels corrected using ChemGeek's method. But my pH levels always rise. I discovered that by shocking with mps once a week and using at least some mps after each soak, I CAN maintain FC levels, although sometimes not for the whole 24 hours. So, I think my method of adding some bleach each morning is a fairly safe method. By the time I soak typically at 8 or 9pm, I still have some FC levels. Maybe I don't have any FC levels at, say, 4am, but it's going to get a good dose of chlorine around 7:30 am daily. Since I have low CYA levels, I'm thinking it's a very effective kill at that point. I like my method (bleach is also more inexpensive, but a little harder to handle, too), but the only drawbacks are fighting the rising pH and having to make daily additions of bleach. Is there some other, more "trouble free" method? One that doesn't require daily additions or constant monitoring of pH? Even if it costs more that liquid bleach, I might try it.

Thanks,

David

I didn't mean to put any insults in my post. I'm betting that most hot tub dealers are not chemists and can't balance a chemical equation, that's not an insult but a speculation. And I'm not angry but just sorta amused that posts supporting dichlor and ignoring cya seem so conclusive. I honestly don't think it's a huge problem but to those that are really concerned that their water be the safest and best that it can be and are using chlorine I think that being aware of cya is reasonable. I haven't found any information showing that cya is a non-issue. I have found information showing that it is. I would like to see any information showing that sanitation does not decrease with increased cya use. Or even some federal or state agencies that have adopted the stance that cya is a non-issue. I do find a lot of states require pools to not be over 100ppm cya. This in itself says there is a reason for that.

Thanks for clearing that up. Sorry if I saw insults were none were intended. Many of the people I deal with have become friends over the years, not just business acquaintances. I'm proud to know them on both levels, so was hurt when I thought it was an insult. Again, sorry. I will admit that "non-issue" could be too strong, but the whole "sky is falling" approach is way to drastic as well. Everything I've found does state that the effectiveness of chlorine does go down with high cya levels. Most tests involving chlorine are at .5 fc with 99.99% kill in under 30 seconds. This won't happen with high cya levels which is why spas are supposed to be maintained at 2-5 ppm fc. If I was using dichlor alone, there is no way I'd accept .5 fc. I do not believe that would be safe. I had proof of this when using bleach. Take any bias I have out of the bleach issue. For me, I could not maintain fc with bleach so I ended up with cloudy, smelly water. I'm sure if I used only dichlor and ran .5 fc I would end up with roughly the same situation. I haven't ran into any problems with dichlor if I keep my fc levels up and I don't expect to. The only other point that I'd make is that when getting info. from the cdc and epa it's important to remember they are dealing with public health. The majority of us would have our kitchens shut down if the health inspector came in. That's not to say we aren't clean. We prepare meals and make a plate of leftovers for whoever isn't home and they eat it later. We don't stick a thermometer in it to make sure it's at the correct temperature until they get home. We prepare food for friends and family without wearing gloves or hairnets, etc. Restaurants here can't serve eggs with runny yolks or beef cooked less than medium, but we do it in our homes all the time. When dealing with public health and liability, the stakes are a little higher and the rules a little stricter. No doubt there are states with guidelines for public swimming facilities regarding cya, there are many more with guidelines for TDS. Here, a public pool is shut down if the TDS are too high, but no parameters for cya. I can't remember the exact figures, I'd have to look, but bleach sends TDS through the roof. While someone might want to see me as a champion of dichlor, I'm actually just trying to champion common sense. One can't cause hysteria over cya while ignoring TDS. To be quite honest, I think bromine is the most logical sanitizer for spas. I don't use it because it makes me itch and my skin smells. Even though I don't use it, I think it's a great product.