I have gone away for two week and just shut everything off during the heat of summer (July). When I returned the pool was only slightly cloudy (but no chlorine left) which was fixed by a shock with bleach.

My secret? I have 50 ppm borates in my pool!

I intend to do the same this year in 3 weeks. Will post what the pool looks like when I get back. I suspect it will be the same as in the past, only a bit cloudy and no visible green! I already have the gallon of bleach in the garage in anticipation of my return.