Shock it. It's possible that you already had a bloom starting before the CYA addition, or that the party introduced more of a bacterial load than the superchlorination was able to cope with, but if your water is green tinged and not clear, you definitely need to shock it. Vacuuming the algae up doesn't really get it out of your system unless you kill it first--even if you backwash, it doesn't all wash out and it only takes a little to keep the algae growing in your pool..

Janet