High TA

[Tman122]

There's alot of folks who use "alternative sanitizers" and brag about water that's years old blah blah blah but as you stated, there's nothing like fresh water, nothing. I find very little info on CYA except I heard of one guy who tackles the problem by using triclor every other time to keep it lower. Not sure about that idea but it seems theres very little available regarding how to reduce it. The MPS and dichlor thing we both do seems to help also, but dichlor as a shock or sanitizer is far superior to MPS. Soak relax and ponder the CYA

[Lori]

Amen, Tony and Roger!

Nothing like fresh water!!!  

[Chas]

Some things never change! This old thread is still 'fresh' today -=- pH and TA, combined, are called "Water Balance." Get that right, and the rest is a breeze.

 

[chem geek]

Yes, and it's such a shame that even today there is still inaccurate info in the pool/spa industry regarding the basics.  The following describes such misconceptions and gives the truth as has been properly espoused on this and some other forums.

• Total Alkalinity (TA), specifically the carbonates, are a SOURCE of rising pH in their own right due to carbon dioxide outgassing.  So if the pH tends to rise, then get the TA lower and do not try and raise it (even if it needs to be at 50 ppm to have the pH slow down from rising).  The standard advice of TA being a pH buffer so "more is better" is simply pure bunk because it is a half-truth.  A higher TA is useful when the pH tends to drop over time due to acid or net-acidic chlorine additions, but it is like a see-saw so it's all about balance.  If the pH tends to rise over time, then target a lower TA level; if the pH tends to drop over time, then target a higher TA level.
• A pH buffer that is NOT a source of rising pH is borates, so use of 50 ppm Borates (as in ProTeam® Gentle Spa) can help reduce the rate of pH change without contributing to its rise and provide pH buffering in situations where one needs to keep the TA lower.  There are also phosphate buffers that work in a similar fashion.
• The consumption/usage of chlorine is acidic so this needs to be taken into account when looking at various chlorine sources.  Bleach is close to pH neutral when accounting for such consumption/usage (i.e. it is only high in pH upon addition) so the rise in pH is from too high a TA, not from the bleach.  Dichlor is net acidic (i.e. it is only near neutral upon addition) so needs a TA that is not too low in order to keep the pH relatively stable, but over time the TA level will drop so Alkalinity Up (bicarbonate or baking soda) needs to be added as needed.  Trichlor is even more net acidic so needs an even higher TA level for pH balance and will lower the TA more quickly (normally, Trichlor is not recommended for spas, only for pools).  Bromine tabs are also net acidic.