As I discovered last winter, the air stone will freeze in very cold weather. I just remove it and rig the tubing in the slit of the Vexilar float as in the original pic Nice things about the Clam Aerator are: runs all day in very cold weather, has USB cable with AC wall plug, when using all day for minnows it has the circuitry to run all night while plugged in and is fully charged in the morning.