We just got back from a week in the Mountains and I found my TC and CC to be at 0.
I use a stenner pump and tank on a separate timer from the pool. While gone the timer for the stenner pump lost all it's settings for run times; So no chlorine was added. I don't know what day it stopped working - but looking at my chlorine tank it is still almost full meaning no chlorine was added for most of the week!!
Amazingly the pool water is still clear.
Do I need to shock - or just get the TC back to were it belongs?