testing while shocking

Westovers

LifeTime Supporter
May 31, 2009
83
Austin, Texas
#1
I've read that testing pH is not possible while shocking. Are there any other tests that are influenced or made invalid by shocking that we should know about? Can we trust every other test while shocking besides pH?
 

Richard320

TFP Expert
LifeTime Supporter
Jan 6, 2010
20,327
San Dimas, CA (LA County)
#2
pH will llikely be off a little. TA will go blue-to-yellow instead of green-to-red. Seems like CH is also very pale and hard to read when I've done it with high FC.
I think the chlorine bleaches out the dyes used in the indicators.