Suction cups can be tricky... the epoxy hardens, so it would better for decorations. I just wipe down my suction cups when they stop working well. I also use several of them at the same time.
I've been lucky that my RES keep away from the intake tubes. If they were to aggressive towards it, I would probably use my own PVC pipe or a rigid, but flexible tube.
CuactusJohn5 I have the same problem, my turtle is obsessed with pulling his heater off the wall, lol. But, I just stick it back on, that lasts about a week, lol. Steve, your a lucky man, lol