My IG in Northwest Louisiana stays open year round....we get very few consecutive nights below freezing here. When the water temp gets below 60 or so, I shock it and clean out any debris in it, and decrease my pump time to a couple of hours a day. If the weather is to get below 30 degrees, I run the pump at night and just shut it off in the mornings. Have done that for 5 winters, and have never had any problem except that I replace my pressure gauge yearly in the spring...once it gets wet and cold, it sticks and no longer works...no big deal. I run my Polaris once every couple of weeks, and find that my bleach usage drops to a little over a gallon every 10 days to 2 weeks. Much easier than closing, and that way when my water gets warm enough to swim, we're in the pool!

Janet