I was changing my filter socks today down stairs so I turned off the pumps to make it easier. With the pumps off I noticed how quiet the fish room was, or more how loud the pumps were when being on. I decided that it may be a good idea to clean my main pump since it was off and it seemed to be the cause of vibration noise. When i pulled the cover off i got instant gratification and dissatisfaction at the same time. I was pleased to see the chunks of rock in the impeller but also upset that i hadn't installed my inlet screens before I did weeks ago, which means that my system had been running with lower flow and added stress for weeks. All in all I feel good about cleaning the pump. Is your pump clean? When is the last time you cleaned it? 
