Aerate Aquarium Without Air Pump

Good aeration in your fish tank is essential for the survival of your fish. Fish need to breathe in fresh, clean air just like other animals including humans. Lack of dissolved oxygen in the tank water means your fish will not be able to breathe and this can be detrimental to its well-being.

However, to have your tank water aerated is not an easy task especially if you don’t have a pump to facilitate this exercise.

There could be some underlying reasons why you cannot use an air pump to aerate your aquarium. Some of the reasons could be lack of space in your fish tank to install your air pump, the pump is too costly for you or you just don’t need it.

Despite your tank not having its own air pump, you can still make sure that the water inside the tank is aerated for your fish. But the million-dollar question is, “how can you do it?

This article will answer that question in a more simplistic and comprehensive manner so you may know how to aerate your aquarium without necessarily using an air pump. Find out more in the subsequent sections of this discussion below:

The differences Between Aeration and Oxygenation

First things first, you need to draw a line between aeration and oxygenation. Oxygenation describes the amount of oxygen that is dissolved in water. On the other hand, aeration involves oxygenation and it entails the flow of water.

In simpler terms, water movement will greatly influence the overall process of aeration. For instance, oxygenators have the ability to add some oxygen into a certain amount of water in a fish tank but do not disperse it as a result of a lower flow rate.

Aerators are known to produce some oxygen along with lots of flow of water. This way, your fish tank gets aerated to meet one of the basic requirements for the survival of your fish. Aeration is essential because it ensures even distribution of oxygen in the tank for the fish to breath. So, what happens when you don’t have a pump?

How to Aerate Your Aquarium without Using a Pump?

The fact that you don’t have an air pump to facilitate aeration does not mean that your fish in the tank have to suffer. That is why you need to improvise simple ways of ensuring that your aquarium is well aerated to keep your fish alive and active all the time. Use the following tips and get your job done:

1. The Cup Method

Do you know that your cup or pitcher can become an essential tool to help you aerate your aquarium? If not, then you should give it a second thought and see the outcome. Just fill the cup or pitcher with the aquarium and lift it high before pouring the same water back in the tank. The concept here is that water is likely to pick some amount of oxygen while flowing back into the tank. In the process, oxygenated water from the cup will mix and insert oxygen in the water tank in this simple way.

Keep in mind that the higher up the water is poured, the deep it flows back into the tank, thus picking more oxygen and aerating the tank. You can repeat this process as much as you possibly can to ensure that all the water in the tank is well aerated and oxygenated for your fish. During the process, you may have to place some kind of plate at the bottom to protect the substrate from being disrupted as a result of pouring and mixing water in the tank.

2. Use a Good Filter

Your filter can make a big difference when it comes to aerating your tank. This essential part of your aquarium can be transformed into a means of aeration and oxygenation for your fish tank. In simple words, you can use your powerful filter to generate a substantial amount of oxygen while water is flowing in and out of the tank.

The higher water flow rate of your filter will determine the amount of water that is aerated due to its powerful pressure. To achieve this goal, ensure that your tank has a more powerful filter that is kept clean all the time. When your filter is clean, you can rest assured that more water will flow through it into your tank. At the same time, the flowing water will pick some oxygen in the air and diffuse it in the tank water, thus improving aeration and oxygenation.

3. Waterfall Filters and Spray Bars

Waterfall filters or spray bars can play a key role in aerating and oxygenating your tank. This method can work pretty well whereby water flowing down off the waterfall filter or spray bar picks oxygen and mixes it with the rest of the tank water. In addition, the flow of water from certain heights is likely to propel the water towards the aquarium, thus creating an aerated and oxygenated environment.

4. Plants can also be Useful

One of the best and easiest means of adding some oxygen into your tank water is by inserting more plants into your fish tank. Plants are known to take up carbon dioxide and release oxygen at certain times of the day and this is a good way of aerating and oxygenating your aquarium.

During the process of photosynthesis, plants take in carbon dioxide and release oxygen along with other by-products of the same process. Therefore, the higher the number of plants in your aquarium, the higher the amount of oxygen released into the water.

What about the means to circulate the oxygen in water? At this point, the water flow is not so important because plants are already spread throughout the aquarium to ensure that oxygen is evenly distributed.

Take note that the reverse of this entire process takes place when the lights are not there. So, you must ensure that the number of plants in the aquarium is less during the night to maintain levels of oxygen in the water. If left in the water for too long, plants can decrease the amount of aeration and oxygenation in the tank.

5. Addition of more Fish to the Tank

Addition of more fish to the aquarium may sound like an odd idea but it can work pretty well when it comes to aeration and oxygenation of your tank. It is true that fish breathe in oxygen and releases carbon dioxide in the process. So, this means that they take up more oxygen rather than increasing it during their respiration process. This way, they create a deficit of oxygen that they use during their breathing in exercise. But keep in your mind that aeration and oxygenation are two different terms.

The presence of fast swimming and active fish in the tank water serves as a means by which water is mixed. Their movement back and forth is believed to carry the oxygen-rich water from one section of the tank to the other and from top to bottom. This frequent movement of fish facilitates and improves the aeration of the tank water for all the fish to breathe and thrive well.

6. Use a Wide and Shallow Fish Tank

Another simple way of improving the oxygenation and aeration in your fish tank is the use of the right tank. The ideal tank should be able to allow adequate water flow while enhancing the aeration. There is always a higher concentration of oxygen in the fish tank near the top. This is the point where water touches the air hence higher oxygen concentrations.

If your tank is narrow and deep it is likely that you will need a powerful air pump to aerate every section of it. For this type of aquarium, only the topmost area will be oxygenated and aerated as opposed to the deepest areas of your tank. This is not good news because different fish species occupy different regions of the tank. For instance, there are surface dwellers, mid-level dwellers, and bottom dwellers. So, if your tank is deep and narrow and without an air pump, you will be denying some of your fish enough oxygen.

To solve this problem, you will have to look for a wide and shallow tank to keep your fish in it. This type of fish tank creates a larger surface area for water to get into contact with the air above it. In short, the wider your fish tank is the better its water will touch the air. In return, more oxygen will diffuse in water thus improving aeration. Proper aeration and oxygenation are some of the key factors that influence the survival of your fish in the aquarium.

Final Thought

Every aquarium needs to be well aerated and that’s why oxygenation and aeration are an integral part of any given fish tank. Make sure that your fish is well aerated all the time to keep it alive and comfortable throughout. It doesn’t matter whether you have a pump or not, provided that you are determined to keep your aquarium aerated. Even without a pump, you can still achieve this feat using any or a combination of the methods mentioned above. After all, the end justifies the means and your fish will never lack oxygen even in a single moment.

Written by Fabian

Hey, I'm Fabian, chief editor at Aquarium Nexus. I really enjoy the aquarium hobby and love sharing my experience with others. If you have any questions feel free to contact me or leave a comment below.


  1. Pierre Pequegnat Reply

    Hi Fabian,

    Thanks for your article. I am a newbie, and started a 2.5 fishbowl (dirty, and fully planted) about 10 days ago. I have no filter; no aerator. I am concerned about the amount of air (O2 and CO2) in the water for the plants, as I am currently not doing water changes (i.e. still at Ammonia 0, Nitrites 0, Nitrates 0).

    Short of doing water changes (which I don’t want to do until I get some Ammonia to start a cycle), I only see one solution in your article: pour some water from a height.

    As a suggestion, I am going to give my wine aerator a try. It is a venturi tube and so it should enhance the amount of air infused. As my fishbowl is just 2.5 gallons, I am thinking that the SAE (Standard Aeration Efficiency) will be better and just a half gallon of fishbowl water cycled through the wine aerator would likely equate to at least a 20% water change, if not higher. The tube would also allow me to significantly reduce the height from which I had to pour the water into my shallow (dirty) fishbowl.

    I tried sourcing some engineering papers online and there are some studies and white papers, but nothing that speaks specifically to wine aerators and their SAE efficiency (vs pouring water from a height).

    The key question, which none of the documents address, is “using a Vinturi V1010 wine aerator (on amazon), how much air is added; and how much water (in percentage terms), and how often should one aerate a planted fishbowl with no ammonia.

    Probably not worth the work to figure it out and the sooner or later I’ll know something. Either I get some ammonia and start water changes, or my plants die along with the way.

    Given the difficulty that many newbies have with cycling, it’s surprising how little information is really available about what happens in small fishbowl tanks during the first few weeks of cycling.

    Just thinking out loud.

    Again, thanks for your article. I hope my suggestion of using a wine aerator helps your audience.



    • avatar
      Fabian Reply

      Hey Pierre, thank you for your feedback! I never thought of using a wine aerator for any of my tanks, but it is a pretty cool idea.

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