Make sure your chlorinator has all the air bled out of it- otherwise the pucks are just sitting in an air column. Twist the top until water starts coming out then close. No bleach! But a liquid chlorine for pools is OK. Put some granuals or pucks into the skimmer to raise the chlorine level.

Bleach is a liquid chlorine and what many of us shock with.

Use liquid bleach you can get the 6% stuff at the grocery store or if you go to the pool store they will have the 10 or even 12% stuff. If you use the 6% I would use 2 gallons for every 10,00 gallons. If you use the 12% use 1 gallon for ever 10,00 gallons.
Never put granular or pucks in your skimmer this is one of the worst mistakes you can make. This will be a sure way of ruining your filter or even your heater.

Why do you shock when the level gets low? You only need to do so when combined chlorine is present. 2 cups chlorine will get you about a 1ppm jump in 10,000gals

Thanks for the responses. I added some bleach and that brought it up some. I'll retest today and add some more bleach if necessary.
Thanks!