I've done my routine annual battle to clear the swamp. I use 12% liquid chlor that I can get in 5 gallon jugs. I use this for daily chlorine maint, but also for shocking whenever a bloom starts. Sometimes I pick up the 1-pound bags of 63% cal hypo that Home Depot carries (Super Shock is the name) and add 4 pounds, but that is only during the spring swamp battle..
At any rate, I have clear water, but this year I have what may be mustard algae on the vertical liner areas that will not respond to shocking, nor will it brush off. It is very tough. I've never had a growth that would not brush away.