its not the water level if it was it will fill up with water not foam.
if your skimmer is lifting the lid like the one in that pic you posted it is because the water is set to low in the skimmer and the foam is super dry and not much water in it to help it pop. if you look at the pic you can see dirt way down in the neck of the skimmer meaning the water is real low in it, if it was higher up it would be clean.
close the exit pipe to brg the water in the skimmer (make wetter foam) and it will pop and go in the cup vs lifting it.
if your skimmer is lifting the lid like the one in that pic you posted it is because the water is set to low in the skimmer and the foam is super dry and not much water in it to help it pop. if you look at the pic you can see dirt way down in the neck of the skimmer meaning the water is real low in it, if it was higher up it would be clean.
close the exit pipe to brg the water in the skimmer (make wetter foam) and it will pop and go in the cup vs lifting it.