Many aquarium owners make use of an air pump and air stones in their tanks. These put oxygen into the tank water, so it helps fish to breathe effectively, and it can help plant growth. While there are different kinds of a pump and air stones, these are simple in their manufacture.
The issue on occasions is when you see there is no streaming of bubbles, or the stream is thin and from just one portion of the stone. This leads you to the following.
Air stones stopped working here’s what to do. Depending on whether or not your air stone is producing bubbles, will determine what you need to check. It can be something as simple as pump failure, your air stone is blocked, or it can be your tank is too deep for your air pump.
We will look at each area of how air stones work, and what the reasons for them not working can be. Through some simple detective work, you can find out if you have a simple blockage, or you do indeed require a different air pump.
Air Pump Working But No Bubbles
If you have an air pump, and you have no bubbles coming through your air stone, you do need to find if the pump is working, as it should.
Even if it is vibrating and making a sound like usual, this doesn’t mean the pump is working effectively.
One of the first things to check is there is no kink in your tubing. It sounds obvious, yet things such as this have caught many tank owners out over the years. If there is no kink, you then need to determine if your air stone has a blockage.
The easiest way you can do this is to carefully remove the air stone from the end of the tubing, and push this end under the water surface in your tank. If there are bubbles, then it shows you have an issue with your air stone, and your pump is working correctly.
If you have no bubbles, then this can be more serious.
The way an air pump works in most models is through a small rubber bladder. As the pump runs, this bladder faces compression and decompression many times per second to produce the bubbles.
It will vary between models if you can get replacement parts. If you can open up your pump, you can see the bladder, yet it can be hard to spot any worn parts or tears in the rubber. If you are eagle-eyed, there will be seals leading to the tubes. Sometimes, these pull away from the fitting and create an air leak.
Before condemning your air pump, you need to see if you can reposition the seal securely or if it is possible to buy a replacement bladder. One last thing to check it whether the air intake of your air pump is blocked. You should see a small vent, and depending on where you keep this, they can clog up with dust. All you need is an old toothbrush or toothpick to remove the dust and then recheck your pump.
If neither works, or is possible, it means your pump faces the trash. The most significant issue here is, your fish won’t want to wait too long before they begin to suffer through a lack of oxygen.
Thin Streams of Bubbles from One Area
You can find two reasons why you may only be getting a thin stream of bubbles from one area of your air stone. The primary reason being, your stone is becoming dirty and needs replacing or cleaning (you can see how to clean your air stone later).
The second reason is not that anything is faulty or dirty. An air pump can only deliver so much air to any particular air stone. If you change your air stone into something more substantial, then the pump may not be strong enough to deliver enough air to fill all the holes in your stone.
It can be this, which causes a stream from one side of the stone, and not the other. Air pumps will have a maximum size air stone they can push air through unless they are the more powerful air pumps, which comes with a reducing valve so you can adjust the flow of air that reaches your tank.
Tank Too Deep
When you take into account the size of the air stone and the air pump, there are some occasions where a similar thing happens with deep aquariums. Through a combination of water pressure and long tubing, some air pumps may not be strong enough to overcome this pressure.
If you have a large tank and you are unsure if this is the reason, then raise your air stone toward the surface of your tank to see if it produces any bubbles. If it makes bubbles at the top, then it shows your pump is underpowered for the depth of your tank and the length of tubing you have.
It may be possible to reduce the length of your tube and sit your air pump closer to the top of your aquarium for it to be able to push air down to your air stone.
Cleaning and Rejuvenating Your Air Stone
When you purchase an air stone, they can come with different sized pores. The smaller holes marketed as micropore air stones. You tend to find, the smaller the holes, and the better they can dissolving oxygen into the water of your tank.
The issue here is they tend to block quicker than air stones that have larger holes. You tend to see a reduction in performance at around six weeks of use. Although this will depend on the conditions of your water, the higher the mineral content, the quicker they will clog.
Many tank owners will toss out their air stone and replace it with a new one. However, you can clean them to use again, and save yourself some money in the process.
To clean an air stone thoroughly can take between two and four days, and because of this, it is better if you have two and rotate these, so you always have one ready to exchange.
- Remove the air stone from your tubing carefully, and rinse in fresh water. With an old toothbrush, gently scrub off any buildup on the outside of the stone (be careful the stone doesn’t crumble when you brush it). Rinse again and let the stone dry.
- Place your stone in hot water in a saucepan and boil it on a low heat for ten minutes. Doing this helps to break up the gunk that settles in the inner pores of the stone. Additionally, the hot water sterilizes the stone.
- The third steps require you to mix a 1:3 mixture of household bleach and water. With one part bleach, to three parts of water, soak your stone for 24 hours or up to 48 hours if desired. Bleaching the stone, this way helps to kill microorganisms, which bury themselves deep inside.
- Because you use bleach, you need to rinse your stone thoroughly, so all traces have gone. After rinsing, connect one of the air pipes to your stone, and place it into some clean water. Run your pump for five minutes to help loosen and stubborn grime inside.
- Take the stone from the water and let your pump run for another five minutes. This dries the stone thoroughly and makes sure the last bits of dirt are blown from the pores. Once done, dry your stone for 24-hours before you place it into storage. If you pack it away while damp, you can have mold form, and this can ruin the stone and harm your fish.
The above is the best and most effective method to clean your air stone, although some tank owners soak theirs in vinegar overnight. This will dissolve any mineral buildup that won’t break down in the above method. Calcium lime being the main culprit.
Conclusion
Air pumps and air stones are quite simple in function, and if they stop working, there is usually a straightforward solution to the problem.
At the very worst, it will be a pump failure, and without taking too long, you can purchase a new one. With the above information, you may consider this the best time for an upgrade.
Now, you can get an air pump with multiple valves and will allow you to change the airflow. Adding to this, you will know your air pump will be powerful enough to cope with a larger air stone or to cover a deeper tank.
Either way, you know how you can make sure your fish are healthy and enjoy all the dissolved oxygen in the water.

Hi, my name is Adam and I’m an aquarium enthusiast! I didn’t discover the joys of being an ‘aquarium fanatic’ (as some of my friends call me!) until I was in my 20’s. When I first started out I found it difficult to find all the information I needed so I started this website to compile all the useful information I can think of. Enjoy!
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