I have just replaced approx. 50% of my pool water. I made the mistake of taking my water to be tested at a local pool store where the the numbers are very differnt from my test kit (PS 2333). I thought my CYA was in excess of 100 and CH was running a little high @ 500. The pool has started showing a white scale at the waterline. The pool is a 23,000 gal, in-ground gunite pool w/ spa, DE filter and water falls. I have been trying to lower the pH by addition of 4 cups MA twice a day, but the pH just hangs in at 7.6 for the last 2 days after the addition of a little over a half gallon of acid. Maybe I am being a little too impatient but I was expecting some down movement. My test numbers were as follows:
T- 75 deg. F
Water has good clarity
Bleach used for Chlorination
Is there a reason why my pH would be buffered to where it would not be going down w/ the addition of acid. I do run the water falls for some time to get aeration, but is my pH low enough to be gassing off much CO2?? I am trying to lower my pH down to 7.0- 7.1 to see if it will help soften up some of the scale line for easier removal. Any ideas?