ms, good to see you again!
The algae will sink, if given a chance. If you keep the filter running the water turbulence will slow the sinking, but if you turn off the filter(once you're ~ sure the algae is dead) overnight, the next morning you should be able to vac to waste - a lot of it will collect in the corners/ nooks & cranies that usually have the dirt etc that has to be vacuumed on a regular basis. It helps to brush while the cl is high so that you make sure all the algae has been exposed - also, the bristles on your pool brush are much better at loosening it than the ones on a vac head. Vacuuming to waste keeps the filter from getting mucked up by the algae and having it settle in 'piles' reduces the amount of water you need to waste.