Make it last--lube it!
We all get caught at times on things that should be obvious but we still miss it. A recent case for me was loaning the Eheim 2075 (Pro 3?) to my daughter. Next step was the lever on the tube connecting block turns up broken!
She tells me it was getting stiff to move and she thought it might break?
Big point is that we find things last longer if we lube them BEFORE we break them. A practice that I've used for years is to just wipe on a tiny smear of cheap, unflavored petroleum jelly . Equate brand from Wall-mart is my fav. For about a dollar, I've lubed hundreds of things like the O-rings and most anything that moves against something. On the 2075 filters, one of the main complaints is that the lever breaks when trying to force the ball valves closed.
Doesn't do that if you lube them, so I use a Q-tip to mess a bit of jelly down inside the fitting where we can see the balls and also on the sliding parts where the two little nubs stick out and move when we move the valve.
If you try it, you can feel an immediate difference in the pressure it takes to move. Big point on jelly is that it is almost waterproof and we don't have to worry about it moving on into the tank----just don't get crazy with the amount so that it collects dust and dirt to grime things up.