You may have a partial clog somewhere along the way that is keeping you from getting full suction. Try this - without the power head or rod attached turn on the vacuum, now place the palm of your hand where the rod would normally attached. Does it pull your hand towards it? If so, repeat the process by attaching the rod only. If there wasn’t good suction before attaching the rod, you likely have a clogged filter or collection chamber; try cleaning the filters with some warm water and fully empty the collection chamber. If the suction was good there, but bad after connecting the rod, then you have a clog somewhere in the rod. You might be able to fish it out or break it loose with a straightened coat hanger. If suction was good at both of those places then take a look at the hose that is at the bending point of the power head, here is where that hose will crack (this was the case for mine). A crack in the hose will lead to poor suction. Best of luck fixing the issue.