Don't shock your pool with chlorine tablets.

No. Chlorine tablets are for maintenance, not shocking. They dissolve slowly and contain stabilizer (cyanuric acid) which builds up. Shocking with tablets just adds more stabilizer, eventually making your chlorine less effective. You want a quick, high dose of unstabilized chlorine.

Use granular calcium hypochlorite or liquid chlorine (sodium hypochlorite) for shocking. Follow the label for dosage based on your pool volume. Add it in the evening, run the pump overnight, and test the next morning. Tablets are for the feeder or floater during normal operation.

If you’re stuck with only tablets, you can technically double the dose but you’re just kicking the stabilizer problem down the road. Get the right stuff.