True Alkalinity Readings

May 28, 2015
2
San Diego, Ca.
This website has become my go to resource for all things pool related, so I feel confident I can get an accurate answer on this subject. Have been regularly monitoring chemical levels since a real bad CYA, and just bad water forced me to perform a costly $$$ full drain. Just as a sanity check, I will take a water sample in for a second opinion every two or three weeks to two different local pool stores, one a national chain, and the other a small locally owned business. I'm seeing alkalinity slowly creep up, until it's what I measure as a 140-150 level. Well the local pool store uses a term in their report called "Alkalinity (w/ stabilizer correction), and that takes my 140-150 reading and says it's 114, which is within the band I'm trying to maintain. Maybe I've just missed it, but I've never seen anything on this website that says subtract 25% from your swirling green to red alkalinity measurement. SO my question is, is there anything to this claim that stabilizer adds about 25 points to your alkalinity reading??? My cyuranic acid is at 50.
 
Total Alkalinity is comprised of several types of Alkalinity, including carbonate alkalinity and cyanurate alkalinity. Therefore, there is some basis for the claim if you're looking to find out your carbonate alkalinity, which determines your saturation index and susceptibility to pH rise.

Typically about 1/3 of the CYA is subtracted from the Total Alkalinity to determine carbonate alkalinity.

However, the pool calculator already uses the correction to determine the correct CSI (Calcite Saturation Index).

For the most part, you don't need to worry about adjusted Alkalinity. Just keep the TA where it keeps the pH stable.

What is your fill water TA?
 
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.