Can Fish Choke? Common Causes And Solutions

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It may seem a little odd to think that fish can choke or gulp, but it does happen. Though these charming little creatures spend virtually all their time underwater, this watery environment does not assure them of freedom from dangerous conditions.

Choking occurs as a result of swallowing something too large to pass through the esophagus. This problem occasionally affects humans, as well as fish. Some fish are more likely to choke than others, and there are several things that you can do to reduce the chances that your pet will experience choking or gagging episodes.

Can Fish Choke? Common Causes And Solutions 

Fish can most certainly choke, but there are lots of ways to prevent this from happening in the first place. Here are some of the most common reasons why this phenomenon occurs, and some pointers on what you can do to remedy the situation before!

Food Items That Are Too Large

Many fish enjoy eating larger food items. For instance, live foods such as earthworms, crickets, and some species of fish can be quite desirable. However, if you feed your pet a piece of food that is too large for it to consume safely, they may choke or gag. This is because the fish’s esophagus is too narrow to permit easy passage of larger food items.

In addition, many hobbyists also enjoy feeding food items that expand in the fish’s stomach. This is done to make your pet feel full or increase its caloric intake, but it can also cause choking if these types of foods are too large for the fish to swallow.

Yet another culprit is frozen peas and other vegetables. These are often offered as a cure for constipation or as a treat, but many fish instinctively swallow them whole. This causes smaller species to choke or gulp, which can lead to more severe problems such as blocked intestines or suffocation.

The Solution:

Always feed your fish pieces of food that are no larger than the size of their mouths. A good rule of thumb is to observe your pet’s mouth movement as they are feeding. If they need to open their mouth wide just to take a bite of their meal, you are giving them food that is too large. At this point, it is better to feed them a number of smaller pieces that will be easier for them to swallow.

Another popular guideline is to limit your fish’s food thickness to the size of their eye. If you are following this rule, try cutting larger pieces of food into smaller cubes and distributing them over a period of time instead of offering the entire piece at once.

In addition, you should remember to always select fish food with the correct pellet size. Pay extra attention to the dietary needs of smaller breeds, who would benefit from tinier pellets such as the Hikari Bio-Gold Micro Pellets. Consider fish food alternatives if your fish will benefit from them!

Poor Water Quality

One of the most common causes of choking in pet fish is poor water conditions. Fish can easily choke or gulp when they are exposed to low levels of dissolved oxygen within their tanks. This usually happens as a result of overcrowding, excessive feeding, or insufficient aeration or filtration.

Infrequent water changes are the enemy of every fish owner. Fish waste, decaying food, and other contaminants can easily accumulate within your tank given enough time. This buildup leads to an increase in nitrogenous wastes that can deplete the water of oxygen and cause your fish to choke.

In addition, another problem with low levels of oxygen is that it can cause your fish to produce large amounts of mucus. This happens because the body produces more mucus in an effort to maintain proper oxygen levels. Unfortunately, this problem often leads to gill damage and other long-term problems such as death through suffocation.

The Solution:

Start by performing a 50% water change. This will reduce the number of contaminants in your fish tank and can resolve a number of different problems, including respiratory issues. In addition, make sure that you perform regular water changes on a more frequent basis going forward. For instance, if you normally do a 50% water change once per week, try increasing this to twice per week instead.

Owners of larger fish tanks often use air stones, which introduce more oxygen to the water. These are especially helpful when your filter is not working properly or you have an overstocked tank. Just remember that if the dissolved oxygen in your tank drops below six ppm, you should add another airstone instead of increasing its size.

Using The Wrong Type Of Water

Another common reason for choking and gill damage is the use of city water or untreated tap water. Aquarium water sourced from the city often contains chlorine or chloramine, which damages gills and causes mucus production. If your pets are exposed to untreated water, they will eventually struggle to breathe – resulting in choking or suffocation if nothing is done about it.

City water can also cause pH levels to swing from acidic to basic without warning. The chlorine or chloramine in city water is often responsible for this pH shift, which also takes its toll on fish by damaging their gills. For instance, even if you do not notice any of the telltale signs of impending damage – such as discoloration or reduced mobility – your fish are still suffering on some level.

Seawater is another potential hazard for fish owners. If you are using reef salt mix instead of mixed water, your fish could end up consuming too much sodium or chloride if they are not fully acclimated to this type of water source. Seawater also contains high levels of sulfate. Too much sulfate can cause excessive mucus production, which can cause gill damage and respiratory problems that lead to choking.

The Solution:

Keep water parameters in mind when selecting your water source. If you are using city water, make sure to dechlorinate it first before using it within your aquarium. However, dechlorinating water can be a difficult and time-consuming process, which is why many fish owners opt to use reverse osmosis (RO) or distilled water instead. Check out this article for a full list of water sources you can use in your tank.

If you do not want to go with RO or distilled water, remember that both city and reef salt mixes should only make up about 1/3 of your total aquarium water volume. By doing so, you will be providing your fish with enough water to mimic their natural habitat while also giving them some exposure to different types of water in order to slowly acclimate them.

In addition, you should perform a water change if the pH in your tank drops below 6.5 or climbs above 8.4. Alternatively, consider adding some sodium bicarbonate (baking soda) to your aquarium to stabilize the pH and keep it from spiking or dropping too much at one time.

Some Fish Have Higher Odds Of Choking Than Others

Certain species of fish are more likely to experience choking than others. For example, the peachsonas betta fish is likely to choke on their food because they have labyrinth organs. These are unique organs that allow them to breathe air from the surface of their tank. Unfortunately, these organs also make it easy for them to ingest too much air while feeding – which can lead to choking and suffocation.

Other freshwater fish such as koi fish are also at greater risk of choking because they have a tendency to eat plants. In fact, plants that have gone into the digestive tract of a koi fish will not be broken down and can actually form a barrier between other food particles – which can lead to choking as well as other digestive complications.

In addition, some fish species – such as trout, salmon, and bass – are more likely to choke than other species of fish. This is because these species tend to take in their food quickly, which can cause them to choke if they try to grab something that’s too big for them to swallow. If you’ve ever gone deep water bass fishing, for instance, you may have noticed that bass fish choke on their prey quite often.

The Solution:

When it comes to pets such as bettas and kois, the solution is fairly simple. You just have to refrain from feeding them any type of plant material. In addition, you should also avoid putting your betta fish in a small tank because the lack of space can make it easier for them to choke on their food as well as other dangers such as ammonia poisoning.

In regards to problem species like trout and salmon, try adding some aquarium plants to your aquarium. A lot of fish are instinctively drawn to bright green or brown-colored plants, which can trick them into thinking that they are food. Alternatively, you could feed these types of fish at the same time every day so they are less likely to grab their food quickly and choke on it.

If you are a beginner to the hobby, be sure to do your research and opt for species that are less likely to choke. These include catfish, guppies, goldfish, and angelfish. Not only will this help reduce the risk of choking, but it will also give you a better chance of keeping your fish alive as well as healthy.


Can Fish Choke On Water?

Yes, fish can choke on water. However, this will typically happen if a fish consumes too much air during the process of feeding – which is why it’s called ‘air swallowing’. This phenomenon causes a build-up of air inside the fish’s digestive tract, which can prove to be deadly if not addressed by a veterinarian.

Though the choking isn’t caused by water per se, it is the result of having too much water in their system. In order to help prevent this, you should make sure your fish’s tank has a good filtration system as well as a pump that provides them with gentle water flow.

Can A Goldfish Swallow A Rock?

Goldfish ryuikin underwater in aquarium

Yes, a goldfish can swallow a rock. In fact, a goldfish can choke on all sorts of objects including gravel and substrate because they typically eat their food in large chunks rather than sifting through it for smaller pieces. If you have a habit of feeding your fish live plants or giving them treats, make sure that any objects going down their throats are smooth and safe.

You should also opt for tank decor that is either smooth or in the form of non-toxic ceramics. This will prevent any fish from choking if they decide to ingest gravel, decoration, or substrate. You may not be able to prevent their strange fish behaviors, but you can certainly reduce the risk of choking and other preventable problems.

How Do You Tell If A Fish Is Choking?

There are many symptoms of fish choking, but the most obvious is coughing or hacking. If you notice that your fish has this problem, then there’s a chance they’re partially stuck to another object in their mouth. The best thing you can do at this point is take them out of the water and try to dislodge the object with tweezers or a small net. If it doesn’t come out easily then you should take your fish to an experienced veterinarian immediately.


We hope that this article has given you some insight into the problems that can lead to fish choking. This is a serious predicament that can prove fatal if not treated properly, which is why it’s crucial that they provide them with the best possible care as a means of prevention! Trust us – your fish will thank you later!

Did you find this article helpful? Let us know what you think in the comments below! And if you know someone who would appreciate these tips, please share it with them as well!

Wanda is a second-generation aquarist from the sunny tropics of Malaysia. She has been helping her father with his freshwater tanks since she was a toddler, and has fallen in love with the hobby ever since. A perpetual nomad, Wanda does her best to integrate fish-keeping with her lifestyle, and has taken care of fish in three different continents. She loves how it provides a nice break from the hustle and bustle of life.

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