You walk by your aquarium and notice that one of your fish is sitting at the bottom of the tank and is not showing much movement; it will make you worry as it is not normal. Finding the cause behind such fish behavior and eliminating the issue is necessary to ensure the good health of your fish. So, Why is my fish sitting at the bottom? Let us find out.
Swim bladder disorder and inadequate water parameters and conditions are the primary reason behind fish sitting at the bottom. Other causes include stress, illness, and ammonia poisoning. Ensure isolating new fish, good water conditions, and stable water parameters to prevent such issues.
We will discuss the reason and prevention behind fish sitting at the bottom. Also will discuss when it is normal for a fish to sit at the bottom. So, let us get into it.
Contents
Why do fish sit at the bottom of the tank?
There can be numerous reasons for your fish sitting at the bottom of the tank.
Swimming bladder disorder, ammonia poisoning, inadequate water parameters and conditions, and illness are the most common reasons.
Fish that are not happy with their environment or suffering from illness and injury will show such behavior.
We should always find the reason behind such issues as soon as possible and treat it at early stages as such behavior can indicate some life-threatening condition.
Issues like swim bladder disorder and ammonia poisoning can make your fish suffer from critical conditions if not treated at early stages.
Let us discuss all the reasons and prevention behind such issues.
Is it normal for a fish to sit at the bottom of the tank?
Your fish sitting at the bottom of the tank may be completely normal in some cases.
It is normal for a fish to sit at the bottom of the tank if it is:
- A bottom-dwelling fish
- Sitting at the bottom for a minimal time
- A bottom-feeder fish
- Having a rest
- Newly introduced to the tank
Bottom-dwelling fish
A bottom dwellers like corydoras and plecos will spend most of their at the bottom of the tank.
You will find a bottom dweller fish at the bottom of the tank most of the time as they spend their time scavenging the substrate in search of food.
A corydoras will swim at the surface sometime for a second to gasp air as it is their normal swimming behavior.
Otherwise, a bottom dweller will be at the bottom of the tank most of the time.
Sitting for a minimal time.
We can’t understand the whole scene inside the tank, so it is best to avoid some things at some point.
If your fish is sitting for like seconds and then continuing their regular pattern again, it is normal, and there is nothing to worry about.
Yes, if you find any reason behind that, like physical injury or difference in the appearance of your fish, there might be something wrong.
A bottom-feeder fish
A bottom-feeder fish is also known as a bottom dweller and spend most of its time at the bottom.
It is simple as the fish swim in the area where they get their food.
Sometimes you will notice them gulping food from the surface and scavenging for leftovers on the bottom.
Also read: Are Cory Catfish Bottom Feeders?
Having a rest
Like us, fishes also require rest. Some fishes are diurnal, staying active in the daytime and sleeping at night.
Some are nocturnal, stay active at night, and sleep in the daytime.
So, they may be resting and are completely fine.
Some fishes like corydoras take rest for minutes when they require.
Also read: Is My Fish Dead Or Sleeping?
Newly introduced to the tank.
When you add new fish to your fish tank, they take some time to familiarize themselves and swim freely in the tank.
Until then, they will hide somewhere or remain at the tank’s bottom.
So, give your fish some time to get familiar with the tankmates, and once they locate all the hiding spots and every corner of the tank, you will see them swimming freely.
What are the reasons behind my fish sitting at the bottom of the tank?
All these are the possible reasons for your fish sitting at the bottom of the tank:
- Inadequate water temperature
- Ammonia poisoning
- Swim bladder disorder
- Stress
- Illness
- Poor water conditions
Inadequate water temperature
When talking about inadequate water temperature, there can be two cases, very low water temperature and very high water temperature.
When the temperature is very low, your fish will become lethargic and sit at the bottom of the tank to conserve energy.
Likewise, when the temperature is very high, your fish will become hyperactive and show an erratic swimming pattern.
But, the very high water temperature will result in a lack of oxygen in the water, and most of the oxygen will be present at the bottom of the tank, so you will find your fish at the bottom most of the time.
You must know that sudden changes in water temperature will make your fish come under a high level of stress and become prone to various diseases and parasites.
Ammonia poisoning
Ammonia poisoning is also a common reason behind fish sitting at the bottom of the tank.
Ammonia poisoning happens in the fish tank with an elevated pH level and excess decomposition of organic matter in the water.
This situation can make your fish suffer from a life-threatening condition; in the worst case, they can even pass away.
Your fish will develop red or purple gills, have bloody patches on the body, avoid eating, and become lethargic.
In some cases, you will find them sitting at the bottom of the tank with clamped fins.
Also read: How To Treat Ammonia Poisoning In Fish?
Swim bladder disorder
Swim bladder disorder can also make your fish sit at the bottom of the tank.
There can be various causes of swim bladder disorder, like overfeeding, constipation, parasitic or bacterial infection, blowing itself from a hard object, and gulping air.
When we overfeed our fish, their gastrointestinal tract gets extended, which affects the swim bladder.
Also, when we feed our fish dry foods, it gets extended in the belly when it becomes wet, enlarging the intestinal tract and affecting the swim bladder.
Affected fish cannot maintain their buoyancy and will suffer swimming.
Fish with swim bladder disorder will remain at the bottom of the tank or float at the surface.
Also read: How To Treat Swim Bladder Disease In Cory Catfish?
Stress
Stress can also make your fish show such behavior.
Now, if you are keeping aggressive fish with a peaceful fish, the peaceful fish will hide and stay at the bottom most of the time to protect itself from aggressive fish.
If you keep big fish with small fish, the big fish will try to hunt and eat the smaller ones, making the smaller ones come under stress and try to stay at the bottom or keep hiding.
You should know that fish being under stress for a long time will become weak and prone to various diseases and parasites.
Weak fish will become lethargic and less interested in moving from one place to another.Â
Also read: Why Is My Fish Hiding?
Illness
Illness can also be the reason behind your fish sitting at the bottom of the tank.
Diseases like white spot disease or ich are common parasitic diseases in fishes.
The main cause of the disease in your fish is the failure to isolate new fish in a separate tank.
White spot disease is contagious and can rapidly spread all over the aquarium, affecting all your fish.
Your fish will try to rub themselves with stones, substrates, and other objects to get relief from itchiness.
This will make them swim or sit at the bottom of the tank as they will spend most of their time rubbing against something in the bottom.
Swim bladder disease will also make your fish sit at the bottom of the tank.
Also read: Why Is My Fish losing Its Color?
Poor water conditions
Poor water conditions can also make your fish show such behavior.
Fish living in poor water conditions will never be healthy and will always suffer from issues.
Poor water conditions can result in ammonia poisoning, inadequate pH levels, and many other things that can harm your fish.
Your fish will become stressed living in poor water and lose their appetite.
They will slowly become lethargic and prefer to stay in one spot most of the time.
Also read: Why Is My Fish Not Eating?
How to prevent my fish from such issues?
Ensure all these things to prevent your fish from such situations:
- Provide good water conditions
- Ensure adequate water parameters
- Ensure stable water temperature
- Isolate new fish before adding them to your fish tank.
Good water conditions
Providing your fish with good water conditions will help you prevent them from such situations.
To ensure good water conditions, perform a weekly water change of 35% to keep the water clean.
Consider treating the tap water with a water conditioner to dechlorinate the water.
We recommend using the API water conditioner to treat the water, as it will help you eliminate chlorine, chloramine, ammonia, nitrite, and heavy metals from the water.
You can purchase it from Amazon API TAP WATER CONDITIONER.
Add a good filtration system with biofilter media to clean the water protected from harmful toxins like ammonia and nitrite.
Keep a regular check on ammonia, nitrite, and nitrate levels and make sure to keep ammonia and nitrite at 0ppm, whereas nitrate can be at some point that doesn’t harm your fish.
We recommend using the API freshwater master test kit to check your fish tank’s ammonia, nitrite, nitrate, and pH level, as it shows the accurate result.
You can buy it from amazon: API FRESHWATER MASTER TEST KIT.
You can also add plenty of live aquatic plants to your fish tank to keep the tank clean and well-oxygenated.
Keep your tank clean by removing all the debris from the substrate using a gravel siphon, and you can use a dry cloth to clean the glasses.
Clean your filter monthly to clear the excess waste stored in the filter.
Doing all this will make ensure good water conditions.
Adequate water parameters
Providing your fish with adequate water parameters will prevent them from such issues.
Fish living in a tank with adequate water will be safe from most diseases and will live stress-free.
Ensure to maintain the water temperature, pH, TDS, and water hardness required by your fish.
Most freshwater fish will prefer the water pH level between 6.8-7.8.
Also read: What Is The Ideal pH For Freshwater Aquarium?
Ensure stable water temperature
Maintaining a stable water temperature will be necessary to keep your fish healthy and prevent them from issues.
Unstable water temperature will put your fish under stress and become prone to various diseases and parasites.
Consider adding a heater to your fish tank to stabilize the water temperature.
You should add a heater just below the filter pipe from where filtered water comes to the tank so that the whole tank gets heated instead of the area where the heater is fixed.
Isolate new fish
It is necessary to isolate the new stock of fish before adding them to your home tank.
The new fish may contain contagious diseases that can spread over the tank and harm your fish.
So, consider isolating the new stocks of fish and even invertebrates for one to two weeks before adding them to your home tank.
Once you are sure that the fishes are healthy and not affected by any diseases, you can introduce them to your home tank.
Conclusion:
There can be numerous reasons behind your fish sitting at the bottom, of which the primary reasons are inadequate water conditions and parameters and swim bladder disorder.
Other reasons for such fish behavior can be ammonia poisoning, stress, and illness.
Providing them with good water conditions and adequate water parameters will prevent your fish from showing such behavior.
Isolating new fish for at least a week until you are sure they don’t contain any diseases is necessary for the safety of your fish in the main tank.
However, if your fish is a bottom dweller, resting, sitting for a minimal time every day, and returning to its routine, it is entirely normal, and there is nothing to worry about.