Total Alkalinity is a measure of bi-carbonates, carbonates and hydroxides in the pool and can be tested with a 4 in 1 test kit provided by your builder/installer.
The Australian Standard recommends a range of 80-150ppm.
Low T.A will lead to erosion of pool surfaces and corrosion of equipment. It will also cause the pH levels to be very unstable, so small additions of chemicals can result in major shifts in pH and is sometimes known as “pH bounce”.
Adding buffer or alkalinity increaser will raise the Total Alkalinity.
Adding acid to lower pH will also lower Total Alkalinity.