AG Staypoollizer Premium for Above Ground Pools with Nxgen Flow Control (White) Above Ground Pool Use ( Mounting Hardware Included) Senses Low Water Levels Correcting Automatically 24 Hours A Day 7 Days A Week Water level adjustment is achieved by simply sliding the float assembly on the lower rail to the desired height. Water level adjustment range measured from top of pool deck (approximately 4.00" to 9.0"). Additional water level ranges available please contact JCS customer service for more information. Attaches To A Standard Garden Hose And The Float Design Guarantees The Water Is Where You Want It Most above ground pools are equipped with a ledge or railing around the top edge of the pool averaging from four to twelve inches wide.