I know my numbers were always good cause I tested soo much sometime more than once a week,
While this doesn't assist your immediate problem, I just want to note that the TFP way is to test some parameters such as FC and PH, daily, not weekly. The full test of TA, Ch, CYA cn be considerably less frequent
Secondly, tab use and powder shocking are generally NOT TFP-recommended methods (eg liquid chlorine/bleach instead or swg) for a variety of reasons including cya build up, moving target of the important cya:FC ratio, etc.
If a pool is maintained according to the TFP method, which is:
A) daily FC and ph test in order to
B) maintain FC to CYA ratio (see link in my signature)
And c) control ph
D) using pool calculator to estimate csi in plaster pools
Then there would be no need to "shock" monthly...or possibly ever. If maintenance lapses and there is a need to "shock" then we follow a procedure called Shock Level and Maintain - "slam."
Going forward, whether you are successful in getting the work redone or not, please delve a little more deeply into pool school to maintain your parameters so you can enjoy the "trouble free" part of TFP
Best wishes in getting resolution.
PS None of the foregoing is meant to suggest you water chemistry was necessarily the culprit in the plaster problem...I'll leave that to onbalance to address as he is an expert in this area and regularly helps identify problems in application.
I merely want to clarify the TFP way and the practices we recommend to insure a trouble-free pool
