How To Get Rid Of Bubbles In A Fish Tank7 mins read

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Sydney Perry
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How to get rid of bubbles in a fish tank
Image from Flickr

Every avid aquarist desires to have crystal clear aquarium water, without any strange annoying bubbles. Bubbles in your fish tank are not always bad or good for that matter, and sometimes just a nuisance.

Many times, beginner aquarists will find themselves with many bubbles after setting up an aquarium which is ideally natural, and the most common case of the question “Why are there bubbles in my tank”. Unfortunately, with more advanced aquariums, bubbles may indicate a water parameter issue, chemical or organic protein build-up, and in some cases defective, or improperly installed equipment.

With that said, depending on what the cause of the bubbles in the tank is, there are always ways to clear them or prevent them.

Importance Of Proper Fish Tank Set-Up And Maintenance

In the process of finding the causes and solutions to Bubbles in a Fish tank, it is evident that proper initial tank set-up and regular maintenance are required to prevent harmful or unsightly bubbles, as well as most crucially for your tank inhabitants to remain healthy and content.

Proper tank equipment that is installed correctly will perform at its peak to ensure that water parameters and temperatures are kept to their standards, along with water conditioners and aqua salts. Depending on the fish species you are keeping a heater and filter will be required in most cases, which ideally if not installed correctly, or with new aquariums may cause bubbles.

Regular maintenance and water changes will prevent ammonia buildup and excess waste in your tank which essentially could lead to bubbles indicating toxic levels of ammonia.

Why Are There Bubbles In My Fish Tank

H20, the scientific name for water, consists of a bond between hydrogen and oxygen that is needed in the aquarium. Sometimes oxygen can appear in the form of microbubbles or air bubbles in your tank. Though not always harmful there are cases where bubbles in a Fish tank may be an indication of something that should not be there, or poor water conditions.

Looking a bit further into the reasons for bubbles in a fish tank, there are mainly two types of bubbles found in your fish tank;

1. Micro Bubbles

Micro Bubbles are mainly just very small bubbles, and usually, the bubbles form on the sides of your tank or décor after a water change, because the water may be colder, holding more oxygen. On the other hand, Microbubbles may sometimes come in the form of a foamy residue on the surface caused by organic waste or chemicals that have a protein film around them.

2. Air Bubbles

Are Bubbles on the other hand larger water pockets filled with oxygen, usually as a result of filtration, or an Air Stone in your tank providing oxygen, or because of water agitation? Bubbles often form when liquids are agitated; they are simply oxygen-filled water pockets. Though the air bubbles from a filter, bubbler, or air stone are rather beneficial than harmful, and preferred by aquarists, they may seem unsightly to others.

Causes Of Bubbles In An Aquarium

Causes of bubbles in an aquarium
Noticing bubbles in your tank may simply be your filter causing water agitation, and these bubbles are nothing to worry about. Image from Flickr

Considering the main causes of bubbles in a fish tank, and how they are formed, may also help in terms of preventing or removing them from your tank.

  • New Tank Set-Up – Initially you will commonly see bubbles after you have set up a new fish tank. They may be in the form of small bubbles clinging to the sides of the aquarium and decorations. These are usually caused by oxygen released from new décor, plants, and substrates.
  • Filter – Filters, Air Stones, and Bubblers are methods to introduce dissolved oxygen into an aquarium and are used by aquarists to improve circulation and aeration in their tanks, which is beneficial for the well-being of the tank inhabitants. Noticing bubbles in your tank may simply be your filter causing water agitation, and these bubbles are nothing to worry about.
  • Maintenance – As a new or even advanced aquarist, regular water changes are at the top of the list in maintaining a clean and healthy aquarium. Because of water agitation, and in some cases the new water added being colder than the tank water, small bubbles may be released sticking to décor and the sides of the tank.
  • Oil on Surface – In this case, not the kind of bubbles, or foam rather that you want to see in an aquarium. A foamy top layer or bubbles that have an off-white color are usually caused by natural contaminants such as fish waste, causing a layer of oil and proteins around the bubbles. On the other hand, it could be chemicals, from cleaning agents, or even chemicals used outside the tank, which can be dangerous.
  • Certain Medication – certain medication can cause bubbles that linger for longer, or even bubbles with an unusual shimmer, or foamy structure. These will usually clear with proper water agitation.
  • Dirty Water – Ammonia buildup can be an issue in your tank causing bubbles to appear suddenly, out of nowhere. When the water quality is poor, or there are not enough beneficial bacteria to break down ammonia it can be harmful for your fish, and similarly cause bubbles.
  • Bubble Nests – Sometimes you may have exhausted all rational causes, but still find Bubbles. If you own fish with a labyrinth organ (they can breathe air from surfaces) such as Bettas, or Gouramis, which may be them building bubble nests. Though not the perfect sight in an aquarium bubble nest means the fish are happy in their environment, indicating that they want to breed.
  • Pearling – Pearling is a desirable phenomenon, and is caused by plants releasing oxygen into the water. The oxygen from the live plants is released faster than the water can dissolve and is usually a sign of a very healthy tank.
  • Air Bubbles – Air Bubbles can be seen in the form of regular water-filled air pockets, or microbubbles, as we have mentioned initially. Air bubbles ideally contain only oxygen and are a good sign. They consist of bubbles such as those released by air stones and your filter, water agitation, plants, and water maintenance. Air bubbles are generally not essentially good or bad, depending on their cause.
  • Bubble Algae – Bubbles algae are small greenish-colored bubbles usually covering the surfaces of décor or substrate in your tank, and can sometimes be present in the aquarium filter. Most aquarists do not like the appearance of algae or bubble algae in their tanks and try to eliminate it with chemicals or maintenance.

How To Get Rid Of Bubbles In A Fish Tank

How to get rid of bubbles in a fish tank
Cold water holds more oxygen than warm water, thus if cold water is suddenly heated the oxygen released forms bubbles. Image from Flickr

So, as concluded from the main causes of bubbles in a fish tank, it can now easily be prevented or removed, if the cause has been established.

How To Get Rid Of Air Bubbles In A Fish Tank

Knowing the causes, and even though not all air bubbles are ideally harmful or bad in any way, there are still methods to remove them.

  • Air Bubbles in a New Aquarium – New Aquariums are prone to have some air bubbles that are not harmful in any way but may not look good. Thus, to skip waiting for them to dissipate you can;
    • Rinse or soak all décor and media before adding it to your tank.
    • Fill the aquarium with warmer water initially.
    • Use a scrubber to remove bubbles on the sides of the tank.
    • Perform a few small water changes to remove bubbles from the surface.
  • Air Bubbles from Filter or Air Stones – Air Bubbles from filters, and air stones, especially micro air bubbles may not always be wanted, even though they are beneficial, they can linger for too long. Ensuring that your filter and equipment are securely installed and that there are no leaks where air can escape, will prevent bubbles. Ensure that the equipment is fully submerged, and try to keep your air stone away from the filter to prevent agitation that could cause excess bubbles.
  • Reducing Pearling – Though Pearling is essentially a desirable trait in an aquarium, you can still dislodge and disperse these bubbles from the plants by slightly increasing water flow.
  • Air Bubbles from the Heater – Cold water holds more oxygen than warm water, thus if cold water is suddenly heated the oxygen released forms bubbles. Thus, when using an aquarium heater for the first time, or after a water change, there may be some air bubbles present that will dissipate once the temperatures become more constant.
  • Removing Bubble Nests – Fish species especially bettas, Gouramis, and some Catfish build what are called bubble nests for breeding, and carry on with the instinct regardless if you are breeding them or not. Especially Bettas enjoy building bubble nests as a form of enrichment. Ideally, it could stress them if you remove the bubble nests, or on the other hand keep them busy. When removing bubble nests from the surface just be mindful of how your fish react.

How To Get Rid Of Micro Bubbles In A Fish Tank

How to get rid of micro bubbles in a fish tank
Microbubbles are quite common settling on surfaces in your tank, after a water change. Image from Flickr

Microbubbles are a much smaller form of bubbles that can either be filled with oxygen and are harmless or harmful, as opposed to air bubbles in general.

  • Micro Air Bubbles During Water Changes – Microbubbles are quite common settling on surfaces in your tank, after a water change. Ideally, this happens because the new water added is colder than the tank water. Thus, it would be wise to use heated water rather than cold water to replace water during maintenance.
  • Sealing a Filter Properly – Many times canister filters do not seal properly which allows microbubbles to escape in the aquarium. Depending on the type of canister filter you use, always follow instructions precisely during set-up, and ensure the top is properly sealed. Similarly as mentioned, keep Bubblers and air stones on the other side of the tank, away from the filter to prevent micro air bubbles from forming.
  • Fixing a Leaky Hose Connection – Any hose connection in your tank that is leaky or not sealed at the connections may cause microbubbles and should be fixed properly so that no air gets sucked through the connections.
  • Clearing Oil Bubbles – Oil Bubbles or foam can be cleared by removing them with a paper towel. Prevention is key in this case though. Abstain from using soap and chemicals to clean your tank, or around your tank. Always wash your hands, and do proper tank maintenance to prevent foam bubbles caused by waste, or protein buildup. Similarly, you get a tool referred to as a protein skimmer that can be used to remove organic waste bubbles.
  • Ammonia and Algae Bubbles – Algae buildup is one of the main causes of Ammonia buildup as most aquarists reach for chemical solutions to reduce algae, which in turn causes an ammonia spike, because of dead algae. A. Bubbles forming on dead algae are most likely ammonia bubbles that are very harmful. In this case, try to remove all the dead algae and do regular water changes, testing water parameters, and checking periodically to improve water conditions.
  • Tank Maintenance – Keeping your tank clean, and always washing any new décor before adding it will help to prevent bubbles caused by dirt from dust and oil particles, or waste materials.
  • Removing Algae Bubbles – Also known as Bubble Algae (Valonia ventricosa) is a natural bubble formation on live algae with a greenish color. Cleaning algae with a scrubber on investing in algae-eating fish and snails may help keep algae under control.
  • Improve Water Quality – In some instances, poor quality water with parameters that are not ideal can also result in the form of microbubbles or even foam. Keeping water parameters in check and performing regular maintenance will ensure that there is a healthy ecosystem in your tank.

Final Thoughts

Even the most advanced aquariums will occasionally have a few bubbles, especially new aquariums that are still cycling. Mostly air bubbles that are clean and clear do not pose any problems but rather indicate higher oxygen levels.

However, when it comes to smaller foamy bubbles caused by chemical or protein buildup, and bubbles caused by ammonia, it means your tank has not established balanced parameters, or that there are harmful chemicals present. On the other hand, you may just have one of the fish species that likes to build bubble nests in your tank.

Frequently Asked Questions

What is Protein Foam in a Fish Tank?
Protein foam is mainly a result of a build-up of organic waste such as fish waste, leftover food, dead plants and algae, or dead fish. You may notice a thin oily film on the surface of your tank. Ideally, protein foam is more prevalent in saltwater aquariums than in freshwater aquariums.
Are Bubbles in a Fish Tank Bad?
Ideally, it will depend on what is causing the bubbles, generally, air bubbles are small oxygen-filled pockets that are more beneficial and neutral than bad. However, trapped dirt or bubbles caused by Ammonia build-up could potentially be detrimental.
Why Are There Bubbles on Top of My Fish Tank?
There are a few reasons that you may be noticing bubbles on the surface of your tank; Water Agitation or bubbles from plants and filters that have risen to the top. Poor water quality, a protein or oil surface trapping bubbles. Bubble nests are created by certain fish species such as Betta fish.
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Tal Halperin

Tal is an avid fish keeper and has been raising ornamental fish for decades. As a little boy, he drove his father crazy to buy him an aquarium with all the necessary equipment. Now, after a career in the field, he has set up Your Aquarium Place to offer the most comprehensive guide to ornamental fish keeping available and share his passion for the different species he has looked after.