Not that you shouldn't get a good vac, but if you keep your chlorine levels high enough based on your CYA you should be able to prevent algae before it grows.

http://www.poolsolutions.com/gd/best...e-chart.html#a

I think I've heard some of the other contributers here praise the "wanda the whale" above ground pool cleaner, but you should wait until one of those folks comments. All my experience is with inground stuff.