issue with eheim pro2 flow rate

[CCLansman]

My eheim has lost a significant amount of flow rate since I purchased it; I do regular maintenance and can’t figure out why it’s getting worse. Do does the impeller magnet become weaker over time or should i replace the tubing or what?

Any info would be much appreciated, thanks!

[Dakota]

by regualr maintenance, does that include removing and cleaning the impeller itself? I know over time, impellers go bad, but not within a couple of years. hrm.... check your tubing? inlet, outlet for clogs? I've had plant matter clog up an output before.