In your pool, each 3 quart jug of 6% bleach is going to raise your chlorine level by 2.5 ppm. It is OK to add bleach while you are filling, but just be sure to have some way to circulate it like stirring it around with a clean broom or something. Or maybe pouring it slowly in front of your hose as you are filling. After you refill and get things circulating, we'll need an updated cya reading to better advise you.