Help! i cleaned this filter after it was sitting in a box in my basement for a while and intended for it to be a filter on my new tank. It was functioning fine while hooked up before however now when i plug it in, there is NO syphon whatsoever. it makes sound when plugged in however is sucking up nothing, the media basket is filled as stated in the manual. Where is hte impeller located in this filter? Any other suggestions to get it working