I'm going to be closing my pool for the first time and (unfortunately) have a CYA level of 100. (A long weird story that I still can't figure out totally.)

If I'm reading correctly I need to shock to 25 according to the "best guess chart", but my Leslies DPD Deluxe Test Kit only goes to 5. How do I test for the higher chlorine to make sure I've hit it with enough bleach?

Thanks for the help!