Tested levels yesterday (w/my new mac daddy kit) and CYA is around 70-85. I am planning on shocking since I have visible algae. My pool is situated East to West so it gets full sun pretty much all day and temps stay in the 100+ here. Should I just precede with using the 10 gallons of 10% bleach (my FC is darn near 0) to start the process or should I drain some water off. It doesnt seem to make a difference on amount of bleach, using the pool calculator.