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Why Is My Angel Fish Gasping At The Surface? 5 Possible Reasons

Lindsey Stanton Profile Picture

By Lindsey Stanton

Koi Angelfish going to the surface

My little angelfish are gasping at the surface! What do I do? Yeah, it can be pretty scary to see your angelfish, or any other fish for that matter, gasping at the surface. So, why are my angelfish gasping at the surface? Do angelfish need air bubbles?

There are a few causes that can lead to angelfish gasping for air, the most common cause is improper aeration and oxygenation, but it can also be due to poor water quality, improper temperature, or simply the fish is hungry.



The 5 Reasons Why Your Angel Fish Is Gasping At the Surface

Yes, it can be a pretty scary sight to find your angelfish gasping at the surface, and no, this is not normal at all. You may have heard of labyrinth fish. These are fish that have a special breathing apparatus, much like the human lungs, which allow them to breathe gaseous air, just like we do.

However, no, the angelfish is not a labyrinth fish, and it can take in oxygen from the air as we can. The angelfish needs to suck in all of the oxygen it breathes through the water using its gills.

1. Not Enough Dissolved Oxygen In the Water

The first and most common reason why you might find your angelfish gasping at the surface is because they need to breathe, but there is not enough dissolved oxygen in the water. Since angelfish are not labyrinth fish, they need to absorb all oxygen through their gills from the water. If there is not enough dissolved oxygen in the water, they will move to the parts of the water that contain the highest concentration of dissolved oxygen.

Oxygen is a gas, so it rises, which means that the surface of your aquarium will have more oxygen present than the bottom. Therefore, the most likely culprit here is a lack of dissolved oxygen, which then forces your fish to the top in search of more oxygen-rich waters.

The easy solution here is to add an air pump and a bubble or air stone in order to oxygenate and aerate the water. Remember that you want the level of dissolved oxygen in the aquarium to be around 8 PPM.

2. Poor Water Quality

green algae aquarium
Image Credit: vincenzo palma, Shutterstock

Another reason why your angelfish may be gasping at the surface is due to poor water quality. This is especially the case when you do not have a good filtration unit, an old and dirty filter, or just no filter at all.

It can also occur if you have a large population of fish in the tank combined with a filter that is too small and cannot keep up with aquarium filtration needs. The worst things here are ammonia, nitrates, and nitrites, which occur when fish waste, plants, and food are left in the aquarium, break down, rot, and release these substances.

Ammonia & Other Substances

Even small amounts of ammonia and these other substances can be extremely harmful to fish and usually lethal if left unchecked.

While it is hard to know what fish feel when they swim in waters of subpar quality, with a lot of ammonia, it is assumed that it produces a burning sensation and makes it very hard for the fish to breathe. Simply put, they go to the surface in search of cleaner waters and easier breathing conditions.

The simple solution here is to upgrade your filter or just clean out your old one, replace the media, and ensure that it can handle the proper amount of water for your aquarium.

3. Bad Water Temperature

The next reason why you might see your betta fish gasping at the surface is due to the water is either too hot or too cold for it to live comfortably.

Now, this is usually more the case with water that is too warm, but it can also happen when the water is too cold. Just for reference, the ideal water temperature for the angelfish is between 23 and 29 degrees Celsius, or between 74 and 84 degrees Fahrenheit.

Too Hot or Cold

Water that is either too hot or too cold can cause a number of issues for angelfish, as well as for all aquarium fish in general. As you may have noticed, the angelfish is a tropical warm-water fish, so if the water is too cold for it, it might just be looking for an escape to warmer waters. Water that is too cold will more or less freeze your fish, shut down its organs, and eventually kill it.

Water that is too warm, under some circumstances, can be even worse than water that is too cold and cause even more severe issues for your angelfish.

Either way, if the water is too warm, the angelfish might be looking for a way out so it can cool down if it is gasping at the top. Do keep in mind that water that is very warm also holds less dissolved oxygen than cooler water, so this could be contributing to the issue as well.

Whatever the case, you need to find a way to get the aquarium water to the ideal temperature for your angelfish.

4. A Lack of Aeration

albino angelfish
Image Credit: shepherdsatellite, Shutterstock

One thing to keep in mind here is that there is a difference between oxygenation and aeration. Oxygenation is how much dissolved oxygen is in the water in total. However, aeration is how well that oxygen gets spread around in the aquarium.

For example, the water near the surface might have ample amounts of dissolved oxygen, but you have no water flow going on to move that oxygen around and aerate the whole tank.

This could be another reason why your angelfish are gasping at the surface. The solution here is to get a stronger water pump or some kind of device that creates some water movement so that the oxygen spreads around more, thus creating a fully aerated aquarium.

5. Looking for Food

The other reason why your angelfish may be gasping at the surface, or at least looks like it is gasping, is because it is hungry and looking for food. Keep in mind that this is by far the least likely cause of your angelfish gasping at the surface, but it is a possibility nonetheless.

To be fair, it might look like it is gasping, but in all reality, it may just be looking for food. Of course, the solution here is to ensure that you are providing your angelfish with the right food and with enough of it too.

aquarium plant divider

Do Angelfish Need Air Bubbles?

The short answer to this question is no, not really. Now, all fish, of course, require there to be oxygen in the tank. That much is a given.

However, most well-kept aquariums will always have adequate dissolved oxygen levels in the water to sustain all fish, including angelfish. An aquarium with a large surface area, or in other words, if there is a lot of surface contact between air and water, should be fine.

Moreover, a good filtration unit, especially one with a waterfall, will help to oxygenate the water. Also, living plants will engage in photosynthesis and oxygenate the water, too. In the past, we’ve gone over our favorite plants for Angelfish.

If you have some plants, the tank is not overcrowded with fish, and you have a good filter, the aquarium should have more than enough dissolved oxygen within it. So no, when it comes down to it, your angelfish does not require bubbles, a bubbler, or an air stone. With that being said, bubbles coming from an airstone certainly won’t hurt.

Now, if you have a relatively small fish tank with lots of inhabitants, a low power filter, and not many plants, then yes, your aquarium may not have enough dissolved oxygen for the angel fish, in which case they will need additional oxygen infusion, usually from an air bubbler or air stone.

Moving water waves and bubbles bursting in the aquarium
Image Credit: boomkee2532, Shutterstock



The bottom line here is that there are a few different reasons why your angelfish is gasping or appearing to be gasping at the surface. It could be because of poor water quality, poor temperatures because it is looking for food, a lack of proper aeration, or a lack of dissolved oxygen.

As we mentioned at the beginning, the most common reason is related to improper aeration and oxygenation, so those are the first causes that you should look at.

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Featured Image Credit: RobinsonThomas, Shutterstock

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