My Mag is submerged. There was a foam pad with it but it had a sticky back. I was reluctant to use it since I didn't know if something toxic would leach out of the glue into the tank. For now I have put the pump on styrofoam in the sump, but what I'll do next is buy some rubber padding (the stuff you put under rugs) and see if that helps.

I'm always a little paranoid about what I put in the sump for fear of something toxic getting into the tank. Anybody with some bad experiences or suggestions on what to avoid?