Agree with turning water off. 3 months? Not sure you will have a problem there with evaporation. When we do leave in the summer we still keep the AC 80 - 85, we have lost things (plastic decor) when we use to shut off the AC. To qualify this, our home was built in the 60's cinder block construction no outside facing wall insulation, single pane windows, no trees. So it gets hot in there. When we get back it can take the AC as much as a week 100% to get the temp back down having to cool all the inside furniture and walls.