My neighbor called asking for help. Their pool is green. My Taylor kit says FC is zero, TC is zero, Ph is 7.0 or less, ALK is 80, Cya is less than 30 if any at all, the dot is very visible when the tube is full. I added 3 gallons of Walmart bleach that i had on hand but im wondering where to start. He says he added 5 bags of shock a few days ago, and yet FC is zero.

The pool is a 24 foot AG. Im guessing about 13,000 gallons. Sand filter.

Where should I start?