Using the volume calculator from Bleachcalc, I'm getting about 5300 gallons...does that sound right? If so, your shock level with a CYA <30 is 12-15 ppm. To reach 12 ppm from zero chlorine, you would add 1 gallon of 6% bleach. Once you reach that 12 ppm, then you need to test and add more chlorine to get back up to the 12 ppm, as often as possible--for reference, each 1.5 cups of 6% bleach will raise your FC by 1 ppm, so you can use that as a guide to figure out how much more you need to add. The more consistent you are about maintaining that shock level, the faster the pool will clear. You need to maintain that level until the pool clears, the algae is visibly gone, and you can go from one night to just before sunup the next morning without losing more than 1 ppm of chlorine,.

Janet