All modern aquariums have a water pump, which needs to be cleaned and maintained periodically. But why? What happens when a pump gets dirty? How do you clean a pump? How often do you need to clean your pump? We have the answers for you.

What happens when a pump gets dirty?
Nearly all aquarium pumps are magnetic drive pumps. With these pumps, the motor spins a magnetic drive magnet. This magnet is inside the pump's body and can’t be seen or accessed. On the outside of the pump motor is an impeller (or propeller) that spins around a shaft. The impeller has a magnet that attracts the spinning magnet inside the pump, so it spins too. A cover (volute) covers the impeller and has an inlet or outlet molded into it to direct the water through the pump. Check out this video from Iwaki to see how a magnetic drive pump works.

As the pump runs in an aquarium, a buildup slowly gathers on the spinning impeller and inside the volute. This buildup can slow the pump, reducing flow and forcing it to work harder to maintain the same speed. This increases the pump’s power consumption. Additionally, the buildup on the impeller never happens evenly. Imagine spinning a top as a child. The top normally spins perfectly around its axis, just as a pump impeller should spin perfectly around its shaft. Now imagine what would happen if you glued a small rock on one side of the top and then tried to spin it. The top would now wobble because it is not balanced. In the same manner, as a pump impeller gets dirty, it starts to wobble around the shaft. This causes the pump to be louder and wear unevenly. Ultimately, this uneven wear can damage the pump's internal components, leading to failure and the need to replace parts such as the impeller and impeller shaft.

How do you clean your pump?
For light cleaning, disassemble the pump and clean all of the parts with a toothbrush or other cleaning brush. Sometimes, pumps can get mineral buildup. This is more common in saltwater aquariums. In this case, a cleaning acid such as white vinegar or citric acid will help dissolve any mineral builtup on the pump components. Please see our Using Citric Acid video to learn more about how to clean your pumps with citric acid. Keeping the pumps clean will keep them running quietly and energy-efficient for a long time. If you choose to use Citric Acid, we recommend Inland Seas Citric Acid Pump Cleaner.

How often should you clean your pump?
We recommend cleaning your aquarium pumps with a cleaning acid twice per year. You may want to do a quick clean with a brush more often. Powerheads, which are aquarium pumps that are inside the main aquarium display and used for water movement, often need to be cleaned more frequently because the light inside the display tank encourages algae to grow on them, which leads to powerheads getting dirtier much faster than filter pumps, sump return pumps, or utility pumps.