I will try to take apart the pump to see if it's jammed inside. How do I know if ceramic shaft is broken? It's brand new skimmer. And it's normal for pump to vibrate that cause collection cup cover to make loud vibration noise? Somebow I fixed it by taping the cover to the cup. I think bubble and water running sound is quiet loud I can heard it from other room. So is there any suggestion to reduce the sound? Thanks