I have a Intex 18 x 4 Intex(Inflatable), and need to know the "catch" to keeping the skimmer stationary, I am constantly checking to make sure that it is not floating above the water and sucking air. The ring inflates in the day, and deflates at night, and the mornings are the worst. I have put things in to weight it down but that doesn't help. Any suggestions would be appreciated.