Help Me Revive an Air Pump?

[Saltinthedesert]

Trying to troubleshoot an eheim 200 that’s gotten weaker over time. Anyone know how to get it back to normal strength?

[Cory]

Check the rubber drum looking parts for any tears. You can also try bending those arms outwards a bit. That'll increase the amount of "swing" which is how much air it pushes. But it may run a bit louder. Pretty hard to see whats going on from 1 picture and not in person. Also make sure it's not an airstone getting clogged that is making it run weaker.

[Saltinthedesert]

@Cory

thanks for the reply. Was glad that my intuition was right on bending the arms out, I did that. The rubber inside seems to be in very good condition, no tears or cracks.

both airlines are going to two sponge filters that have been recently cleaned, so no flow issues there. In fact, even with nothing on the end at all all, I can tell that the air pressure coming out is pretty weak.

[gardenman]

Under the rubber drum looking parts in those round plastic cylinders are two little flapper-type valves, two in each cylinder. They serve as check valves for the air and can fail or get dirty, limiting the airflow. If one is bad and you have access to wider rubber bands and a X-Acto knife, you can carve out replacements from the rubber bands using the old ones as a pattern.