There are several possible causes of this issue. Disconnect the tubing from the air pump to see if air is coming out of the pump. If it is, and the air stone or bubble wand is a few months old it may be clogged and need cleaning. Once you have cleaned the stone/wand or replaced it, re-attach it to the pump. If the airline tubing is discolored and brownish, snip off this part and then re-attach the tubing to the pump.
If no air is coming out of the port but there is vibrating/noise, you probably need rubber diaphragms. Open the pump and inspect the large black cups. If they are torn, replace them. Repair kits are available via Amazon, local fish stores, and other online sites.
If the motor is dead, there is a 2 year warranty. You would ship the pump back via the instructions in your manual, along with your receipt if you are still under warranty.
Date published: 2019-02-14