Help with jbj ato - float

[Biff0rz]

The ato is used but has been working great except today I noticed the float was floating on top of the water, the suction cup had let go. Thankfully water didn't dump in. Besides a auction cup is there a better way to secure the float switch in the tank? Note, this is for my coral QT

 

[mfinn]

Mine came with a plastic device that clips over the top wall of my sump.