Air Pump Running But No Bubbles – How to Fix this?

Air pump malfunction is one of the basic problems associated with being a fish owner. Your air pump may not be blowing air bubbles due to many reasons.

If there are no bubbles, the mechanical filter may not be working. The filter’s air pipes could be disconnected, and you may need to repair the filter or replace it. Cleaning your filter is crucial to maintain a steady airflow. Other reasons for malfunctioning air pumps may include broken rubber bladder, air pump placement, and faulty tubing. 

Read on to discover all about malfunctioning air pumps and how to fix them.

What is an Air Pump?

An aquarium air pump is one of the most versatile equipment for your aquarium. The primary function of an aquarium air pump is to blow out air. It uses mechanical filters to force bubbles into your aquarium. By forcing air into the aquarium water, you create stable water currents and also provide oxygen to the aquarium inhabitants. Aquarium fish need fresh oxygen to breathe efficiently.   

Types Of Air Pumps

General Purpose Air Pump

These pumps are ideal for running ornaments, sponge filters, under-gravel filters, and general aeration purposes. Most manufacturers have different sizes available for aquarium enthusiasts. Larger models are perfect for deeper aquariums. They are also great if you want to run multiple air driven devices.

High Output Air Pumps

These pumps are ideal for large aquariums with high-pressure requirements. You can also use them for ponds with large air-stones. High output pumps can have a diaphragm or piston design and are usually louder and use more power than other air pumps.


You don’t need to plug in a battery-powered general air pump. These air pumps are life-savers during power outages or when you want to transport fish. Some Battery powered air pumps perform dual functions. They can operate on A/C power under normal conditions and switch to D/C power during electricity outages.

How to Fix a Faulty Air Pump

Here are some other common fixes for a faulty air pump:

Broken Rubber Bladder

You can easily spot a tear in the rubber bladder by running your finger over the air pump and feeling for an opening. These tears are small, so you have to move the bladder to find any cuts or holes in the rubber. If the rubber bladder is broken, you will need to replace the entire device.

Placement of Air Pump

The solution may be as simple as placing the air pump in a higher position. Adjust the air pump position and see if it helps create more bubbles. 

Kink in the Tubing

When installing your new air pump, make sure that there are no kinks or folds in the tubing. You can run your finger over the tubing to ensure that it’s straight. If the rubber folds over, it can stop the air bubbles.

Cleaning Mechanical Filters

A dirty mechanical filter can also prevent air pumps from blowing bubbles. If you have a mechanical filter, you may also have a sponge that sits inside it. This is the main filter component that you will need to clean. Here’s how you can clean a mechanical filter:

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Siphon or scoop out some water

You will need two cups of water from the tank to clean the filter’s sponge. Avoid using tap or distilled water for the benefit of your fish. Fish are highly sensitive to environmental changes. Tank water will ensure that your fish are happy and comfortable. Use a siphon or a plastic cup to scoop out some water from the tank. Drain it into a medium-sized container or in a bucket.

Unplug the filter

The next step is pretty self-explanatory. Unplug your mechanical filter to avoid electrocuting yourself as you clean it. You can also remove the filter off of your tank and make your life easier. You will also need a bowl, bucket, or sink to avoid spilling water on the floor. 

Clean the sponge or pad

This step is quick and painless if you have a water bowl. You don’t want to leave your fish without a filter for long. All you have to do is wash the entire gunk off of the sponge. You can use your hands and the tank water for deep cleaning. Wash the sponge until the water runs clear. If you don’t want to touch a dirty aquarium, you can wear gloves or hire a professional to do it for you.

*If your sponge is dirty, you can replace it.

Scrub the casing and tubes

Use the leftover tank water in the bowl to clean all other parts of the filter. You can also grab more from the tank if the bowl water is dirty. You can scrub any hard to reach areas by using a filter cleaning brush – cleaning brushes are available at most pet supply stores.

Put the sponge back

The final step is to return the filter to your fish tank. 

Uses of Air Pumps 


Fish require oxygen to survive like many animals. They can “breathe” oxygen from aquarium water. They absorb dissolved oxygen from the tank water through their gills. The aquarium absorbs oxygen at the surface of the water, but this may not always be enough. 

The use of an air pump can increase CO2 and O2 gas exchange. It helps maintain dissolved concentrations of oxygen at safe levels. Air pumps increase the surface agitation by letting air bubbles escape. This helps increase oxygen levels inside the fish tank. Using an air pump with an air stone can create thousands of oxygen bubbles for your fish. 


Many people add an Air Stone (powered by the air pump) to their aquarium to create a beautiful flow of tiny bubbles. You can find various shapes and sizes of air stones on the market. Some air stones and ornaments also have LED lighting for dramatic aquarium effects.


Under-gravel filters, sponge filters, and many other filters use air pumps to function. The air from an air pump helps create water currents with rising air bubbles. It helps draws water through simple filtration devices. This method of powering filters can also provide aerobic bacteria with fresh oxygen. All aquarium inhabitants need oxygen to thrive! 

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Protein Skimmer

Some types of protein skimmers also use an air stone to produce the foam. This helps remove protein and organic waste from the aquarium water. These protein skimmers use wooden air stones and produce small bubbles, which are incredibly efficient.

The Importance of Air Pumps

You may be wondering why an air pump is necessary for your fish tank. We all know that fish require oxygen to survive, but different factors can impact how much oxygen fish receive in your tank:


It’sIt’s harder for oxygen to be available for aquarium inhabitants with higher water temperatures. Water temperature can fluctuate between seasons, so it’s important to have an air-pump. This will ensure efficient oxygen production even in the warmer summer months. 

Population Size

The amount of fish stock in your tank can affect the oxygen levels. Fish size is also a big factor that affects oxygen levels. When you are stocking a densely populated tank, it’s important to install an air pump. It will help produce enough oxygen for all aquarium inhabitants. 


If your tank has excessive organic waste, it will need more oxygen to break down all the waste material. Installing an air pump is a great idea to clean up all the waste.

Air pumps add an extra layer of protection and guarantee the health of your fish. 

Frequently Asked Questions

What causes a lack of oxygen in aquariums?

Excess waste, clogged filters, and algae overgrowth can cause decreased oxygen levels. Breakdown of waste and detritus by the bacteria in the aquarium gravel also uses a large amount of dissolved oxygen. You can install an air pump to ensure a constant oxygen supply for your fish.

Do tetras like air bubbles?

Neon tetras love fresh oxygen bubbles. Air pumps promote aeration and break surface tension by creating water bubbles. We recommend air pumps for a heavily stocked fish tank. Large population size can make oxygen levels deplete quickly. It’s best to get an air pump because you don’t want your neon tetras gasping for oxygen.

Can molly fish live without an air pump?

Mollies can’t survive without oxygen. Anytime the oxygen levels in the aquarium drop, your fish become susceptible to illnesses and diseases.

Can too many air bubbles kill fish?

Try to keep your air bubbles at a minimum. Having air bubbles with too much force can damage fish eggs and cause other accidents. It can stop fish from relaxing and sleeping properly. Plus, high-force bubbles can kill little fish.  

Why is my air pump so noisy?

Worn diaphragms can create excessive noise in air pumps. Other reasons may include the extra pressure on your air pump. Air pumps need to work harder to push air in larger aquariums, which causes more noise.

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Nadine Oraby

My name is Nadine; I am a passionate writer and a pet lover. People usually call me by the nickname “Joy” because they think that I am a positive and joyful person who is a child at heart. My love for animals triggered me to create this blog. Articles are written by vets, pet experts, and me. Thanks for visiting. Your friend, Nadine!

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