Cyanuric Acid and dangers of being too high?

[gores95]

OK so my Taylor Test Kit comes today and I feel like a mad Chemist!  Tested the water and everything is pretty good.  Dosed with two tsp of Dichlor last night and gone this morning.  Maybe should raise PH and TA a little bit.

FC: 0
TC:  .5
PH:  7.2
TA:  70
Hardness:  200
CA:  100+ (should be 30-50)

I did a lot of searching and understand CA and that it is added to Dichlor to prevent the sun from dissipating chlorine.  Some mentioned no big issue until it gets VERY high...200-500 ppm.  Also learned that the only way to lower CA is to either do a full or partial water change and that over time Dichlor users are introducing more and more CA to their tubs with each Dichlor dose.

Here's the issue...a few posters said too high CA could become toxic and whenever I see the term "carcinogenic" it is cause for concern.  The posts I read on this site were from 2004/2005 so has there been any updated info on this subject?  Why don't chemical manufacturers make spa "CA free" chlorine since our covers are closed most of the time and sunlight isn't as much of an issue?

The water is still very clear with very little foaming and the tub is new and was installed with new water on 10/17.  I know Chas' Law and was planning to empty after one month but for the CA to get to 100 after only three weeks is a concern.

Does anyone else measure CA and find this to be an issue?  Am I getting bent out of shape for nothing?

Thanks,

Marc

[windsurfdog]

Don't worry about CA.  It's just not an issue for a tub that gets regular water changes.  By regular water changes, I bet you could go a year or more without changing water and the CA still wouldn't be an issue though TDS probably would.  I've never checked my CA...and I change my water every 4 months.  I think the inclusion of CA test in the 2005 is more for pool testing where CA presence is needed rather than tub testing where it is just a very minor annoyance.

[gores95]

Don't worry about CA.  It's just not an issue for a tub that gets regular water changes.  By regular water changes, I bet you could go a year or more without changing water and the CA still wouldn't be an issue though TDS probably would.  I've never checked my CA...and I change my water every 4 months.  I think the inclusion of CA test in the 2005 is more for pool testing where CA presence is needed rather than tub testing where it is just a very minor annoyance.

I appreciate your response and you are definitely on one side of the argument.  Anyone have a differing opinion?

[Vinny]

Apparently in a pool when CYA reaches about 100 chlorine is less effective. There is something I read (maybe Taylor  book) about a warning of CYA greater than 100 PPM but I probably soak in CYA over 100 after 2 1/2 months.

I agree with windsurfdog, don't worry about it ... if you can't get over the fact it's over 100 then do a partial water change.

[In Canada eh]

gores95

        Very high levels of CYA(200 and up) cans cause whats called chlorine lock, thats when chlorine becomes almost ineffective at the levels found in a tub.  Vinny and Windsurfdog are right, don't worry about it you will change your water before it reaches that high a level

                                            Have fun in the new tub
                        

[IDW]

 

Why don't chemical manufacturers make spa "CA free" chlorine since our covers are closed most of the time and sunlight isn't as much of an issue?

They do. Lithium, Sodium and Calcium Chlorine. Most people use diclor beause it is PH neutral and easy to dissolve. Most chemical companys do not recomend  100ppm CA levels

[Pisces]

I find the same thing. With regular use of dichlor, CA will reach 100 in no time. I like to use lithium hypochlorite to shock with. Lithium hypochlorite has a pH of about 10. I find this useful since regular dichlor use tends to gradually bring the pH down and this tends to even things out. Being an unstablized chlorine it also disipates quicker than dichlor. The only downside when used in this manner is that it takes almost twice as much, volume wise, as dichlor, to reach the same chlorine level and probably adds more to TDS than dichlor, although I haven't found this to be a problem. It's also more expensive than dichlor.  

[gores95]

I find the same thing. With regular use of dichlor, CA will reach 100 in no time. I like to use lithium hypochlorite to shock with. Lithium hypochlorite has a pH of about 10. I find this useful since regular dichlor use tends to gradually bring the pH down and this tends to even things out. Being an unstablized chlorine it also disipates quicker than dichlor. The only downside when used in this manner is that it takes almost twice as much, volume wise, as dichlor, to reach the same chlorine level and probably adds more to TDS than dichlor, although I haven't found this to be a problem. It's also more expensive than dichlor.  

Again the question begs to be answered:  Why don't chemical manufacturers develop Dichlor WITHOUT CYA?  This formula can be used in spas whcih really do not require the CYA.

Marc

[tony]

Again the question begs to be answered:  Why don't chemical manufacturers develop Dichlor WITHOUT CYA?  This formula can be used in spas whcih really do not require the CYA.

Marc

Dichlor is dichlor because of the CYA.  The CYA is part of the composition of dichlor that makes it pH neutral.  If the question is why don't they develop a chlorine that does not include CYA, is fast dissolving and is pH neutral, that is different story, but obviously not as simple as it seems.  All sanitizers have their plusses and minuses...not a one is perfect.  As was mentioned, the closest non stabilized chlorine that is acceptable for use in a spa is lithium, but that has its own drawbacks.

If you use Nature2 or a Frog as a helper, keep your after use chlorine to a minium and shock with non chlorine shock or lithium, you can keep CYA levels under control.

[tileman]

OK so my Taylor Test Kit comes today and I feel like a mad Chemist!  Tested the water and everything is pretty good.  Dosed with two tsp of Dichlor last night and gone this morning.  Maybe should raise PH and TA a little bit.

FC: 0
TC:  .5
PH:  7.2
TA:  70
Hardness:  200
CA:  100+ (should be 30-50)

I did a lot of searching and understand CA and that it is added to Dichlor to prevent the sun from dissipating chlorine.  Some mentioned no big issue until it gets VERY high...200-500 ppm.  Also learned that the only way to lower CA is to either do a full or partial water change and that over time Dichlor users are introducing more and more CA to their tubs with each Dichlor dose.

Here's the issue...a few posters said too high CA could become toxic and whenever I see the term "carcinogenic" it is cause for concern.  The posts I read on this site were from 2004/2005 so has there been any updated info on this subject?  Why don't chemical manufacturers make spa "CA free" chlorine since our covers are closed most of the time and sunlight isn't as much of an issue?

The water is still very clear with very little foaming and the tub is new and was installed with new water on 10/17.  I know Chas' Law and was planning to empty after one month but for the CA to get to 100 after only three weeks is a concern.

Does anyone else measure CA and find this to be an issue?  Am I getting bent out of shape for nothing?

Thanks,

Marc

Marc,
I just found some websites that mention the dangers of a high cyanuric levels. I pasted the info on anne's post Shocking with MPS and FC level.