I have been battling my pool for almost a month.... It is an inground pool ~30000 gal. It was almost black a month ago, the pool store said my ph was high but that would work to our advantage to floc with alum, so I did that with really no results, I went to a different pool store and they had this new product called clearx by Poolife, which is a 2 part shock and floc and I did that on Thurs. I get up Fri. expecting amazing results, but was disappointed, so I started vacuuming blindly to get rid of whatever algae, etc has fallen to the bottom of the pool and I have vacuumed blindly for close to 2hrs Fri, Sat, and Sun. Last night I shocked it with 7lbs of shock the water is cloudy and I'm thinking still may have algae. I can see maybe 2-3 ft down in the water. I have a sample to carry to the pool place today to see what they say. Any help/advice would be greatly appreciated.