After algae clear, when do I stop shock

[waterbear]

Would the shock also make my CYA level read high??
I had the CYA level checked at the local pool 2 weeks ago, and checked it with the 234 kit earlier this week and the level was 30.

I guess the take home message when shocking is not to look at the other chemistry?? Would that be a safe assumption??

Blessings,

Well, high chloinen levels will interfere with both pH and TA tests but they should have minimal effect, if any, on CYA and calcium hardness. However, IMHO, you should not try and balance the water while the chlorine is at shock levels.
The CYA test is somewhat subjective and it is quite possible that the pool store did not give you an accurate reading. Keep tabs on it yourself and see how it goes.