Just a note:
I started this thread because my Eheim 1250 had a definite rattling noise. I noticed everytime I put my hand on top of it and pressed lightly the noise stopped. I figured the whole thing was rattling. Upon closer inspection today I found that if I just touched the front silver looking piece the noise stopped. The problem was just the front silver piece that snaps-on was rattling as the pump vibrated slightly. It made a heck of a racket considering how quiet it is now. What I did was just stuff some tissue paper underneath the silver front silver piece (cap for the intake nozzle) and the rattling stopped altogether.
So, besides rubber gromment on the feet you might want to add a simple piece of foam or something underneath the front silver snap-on cap. Then, be amazed at how quiet it sounds!
