The TA is a titration test. 25ml of pool water, add 5 drops of the reagent and then count drops of the titration agent until it turns from green to red.

I haven't gone out to get any water yet today - my daughters have been high maintenance this morning. I will go buy some distilled water later.

I think I am concerned about the pH from the explanation earlier about the high CL level changes the pH reagent.