I didn't really close my pool this year, just set the pump to come on if the temperature is predicted to get below freezing. I do have a solar cover on it to keep the worst of the dust out of it, though. Anyway, I decided I should probably clean out my filter cartridge. I do not have a valve on the side that goes to the pool from the filter, so I had to stick my arm in the water up to my elbow to take the return eye out and put the plug in the return. The water thermometer read a shade under 50. Brrrr!!! My husband was laughing at me.