Welcome to our forum.
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.
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?
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
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: 0TC: .5PH: 7.2TA: 70Hardness: 200CA: 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