I heard a loud grinding noise coming from the living room, and in my head I was thinking a pump just bit the dust. I have a maxijet on the skimmer and another one on a reactor, so I figured it was my older pump giving up the ghost. I could hear it two rooms away, so I rushed in to check on it. It turns out to be a very brave snail that took on my MP10. It took him a bit to decide not to keep pushing his way into the propeller. He may need an Advil now. He decided to stand down and now all is quiet.