My saltwater chlorinator is not working at all. Water temp is currently 72. Yesterday I brushed some green off of the walls and bottom. Did a daily chlorine test and it was clear as could be at zero. So here I am with no chlorine in the water. I know I need to SLAM but it’s still new to me. First off I have. 4 gallon liquid chlorine jugs and granular packs of shock. How much do I need to add?