Fish communicate their feelings in different ways. We don’t often understand these subtle cues. My first time I tried this hobby was when I noticed a fish that was always lying in the tank. It was something I assumed was just a habit, but it turned out to be ammonia poisoning. The fish had already died by the time I realized it. It was a day too late and a dollar short.

You don’t have to worry yet, there are many reasons for this phenomenon – some good and some not. Let me tell you everything so that you can determine the cause.

Why Is My Fish Laying On Bottom Of Tank?

A fish found on the bottom of a tank is not usually a cause for concern. This is quite normal, especially if your fish lives on the bottom like a catfish. Fish also rest and sleep at the base. If your fish spends a lot of time at the bottom, it is a sign that something is wrong. You may have a stressed fish.

If this is the case you should quarantine the fish immediately until you determine the reason for the problem and then treat the fish accordingly.

These are the possible reasons your fish may be lying on the bottom.

• The water is too hot
• The water temperature is cold
• Your fish has white spots disease
• Your fish has a swim bladder disease
• Your fish isn’t adapting to a new environment
• Ammonia poisoning
• Nitrate poisoning
• Too many current
• The tank’s too small
• The stress on your fish is
• Your fish is lying
• Your fish is asleep
• Your fish lives at the bottom

The Tank Is Too Hot

The most important thing about fishkeeping is to get the water parameters just right. Temperature shocks are very common in fish. Depending on the species, water temperature should be between 75-80degF (24-25degC).

Warm water releases oxygen much faster than cool water. Although your fish might be able to tolerate warmth, they will quickly become sick from a lack of oxygen. The fish will then move to the bottom of their tank where there is more oxygenated water and colder water.

Hot tanks will also help increase the metabolism of your fish, which can lead to increased excrement and ammonia-producing bacteria. The tank’s oxygen level will eventually drop.

Do not rush to lower the temperature if you feel that a hot tank might be a problem. They are susceptible to temperature shocks. You should do this slowly. This can be done with an air conditioner or a fan. An air pump is also useful to add oxygen to the water.

This Tetra Whisper Pump has thousands of glowing reviews on Amazon. They are available in a variety of capacities, ranging from 10 to 100 gallons.

Your fish could die from suffocation if the temperature and water aren’t dropped. To lower the temperature, don’t use ice cubes and ice packs. This will not only shock your fish but also destroy the good bacteria colonies.

If you believe that lighting is to blame, consider switching to LED lights that emit very little heat.

The Water is Cold

Fish can be as dangerous as hot water. Fish, like reptiles or amphibians, are cold-blooded. Fish retain heat from the environment to maintain their body at a comfortable temperature. We cannot stress enough how crucial it is to maintain the right temperature.

The fish’s metabolism is slowed by cold water. However, cold water also slows down the oxygen intake process. Combining these two events causes the fish to become tired and lethargic. Naturally, the fish will eventually swim to the bottom of their tank to rest.

You should gradually raise the temperature to ensure that cold water doesn’t shock the fish.

To slowly increase the temperature, you can use an in-tank heater or a light source. To avoid sudden temperature rises, we recommend only doing one thing at once.

Your fish has white spot disease (Ick).

White spot disease (also known as ick) is one of the most serious infections in fishkeeping. Ick is extremely contagious and can be transmitted to other fish without the need for a host. It is caused by a parasite called ichthyophthirius multfiliis. The symptoms include tiny white spots scattered across the body.

Ich causes the fish to itch, and it then attempts to soothe itself by rubbing its skin against decors and substrate. This is why your fish hangs out at the bottom more often.

This is according to the University of Florida the most common reason for fish that lie on the bottom of the aquarium.

It is crucial to get rid of the disease as soon as possible. If you don’t, your fish tank will become a food source for worms.

If the temperature is not right, the fish is stressed or if their diet is poor, they are more likely to get icky. Other signs include itching and white spots, heavy breathing, loss of appetite, and unusual hiding behaviors.

If the fish is suffering from ich, raise the temperature of the water by a few degrees. Then use chemical treatment.

You can medicate the fish for up to two weeks depending on its severity.

Here is a link to API Super Ick Cure Remedy, which is suitable for freshwater as well as saltwater fish.

A potassium permanganate solution can also be used to bathe the fish.

This video shows you how to safely give your fish a potassium-permanganate bath:

Your Fish Has Swim Bladder Disease

The swim bladder, which is usually filled with oxygen, acts as a ballast to help fish keep their balance and prevent them from sinking or floating up. Swim bladder disease can cause fish to lose buoyancy, and they will often sink to the bottom of their tank.

A variety of factors can cause a narrowing of the swim bladder, including digestive problems such as constipation and overfeeding.

The condition isn’t fatal, but it can severely stress the fish and cause damage to its immune system.

Other signs that indicate swim bladder disease include distorted buoyancy and a curvilinear back.

You can increase the temperature slightly and fast the fish for three days if you suspect that it is due to a digestive problem. Continue feeding the peas on the fourth day, until they feel better.

If the problem is due to infection, the vet will prescribe a broad-spectrum antibiotic.

The fish surgeon may also remove part of the bladder, or place a small stone to restore balance if the problem is internal.

Your Fish Hasn’t Adapted To New Environment

Fish can become stressed when they are moved to a different environment. Most likely, their home’s water chemistry is significantly different.

If the tank has a hierarchy and pecking orders in place, anxiety will be even more. Most fish that are first introduced to the tank act timidly within the first few days. They hide away and stay alone when possible.

Fish will seek out hiding spots, such as plants or caves, to make sure they feel safe.

If the fish are friends, they will gradually lose their inhibitions to explore the new environment.

If your fish is swimming to the bottom most of the time, that’s normal behavior. If it continues for a long time, you may want to investigate other causes.

Ammonia Poisoning

When fish produce waste, ammonia is invariably produced in a tank. You probably know by now that ammonia can be fatal to fish. If not treated promptly, it can cause chemical burns to the gills that can prove fatal.

Ammonia poisoning is characterized by reddish or purplish-colored gills, red streaks all over the body, lethargy, and a decreased appetite. The fish can die from internal hemorhaging if they aren’t treated promptly.

A freshwater tank should have a level below 1 ppm. This is the acceptable level. Your fish can become poisoned if the levels rise above this level. This happens most often when the tank gets too full or when you are setting up a new tank.

It is important to monitor the tank’s ammonia levels. You can improve your filtration and do weekly water changes to maintain it.

Ammonia poisoning can cause serious illness in fish. Unwell fish can lay down at the bottom of the tank, as you all know.

Here is a link to Seachem’s Ammonia Alert sensor, which continuously monitors ammonia levels. It costs very little and lasts almost a whole year.

Here’s the link for API’s AMMOLOCK Ammonia detoxifier that I used to eliminate all ammonia from the tank.

Nitrate Poisoning

The fish will become tired and sick if they are exposed to high levels of nitrate. Another compound made from fish waste is nitrate. A well-cycled tank with good bacteria will convert ammonia into nitrites. The bacteria will then convert nitrites to nitrate.

Nitrate is less dangerous than nitrite and ammonia, but it can still cause a lot of damage. Even worse, nitrate can be a slow killer.

Nitrate poisoning can often be accompanied by a lack of appetite, lethargy, rapid gill movements, and panting.

Many aquarists agree that a nitrate level of 20-40ppm is safe for freshwater tanks. This dangerous myth is based on the fact that nitrate can be less harmful than ammonia and nitrite.

The nitrate level shouldn’t exceed 10 ppm.

Even if your tank has a high level of nitrate, it is important to not reduce it too much as this could be dangerous for your fish.

There are several ways to reduce slowly the nitrate level:

• Reduce feeding frequency
• Air stones can be added
• Filtration media that removes the nitrate
• Water changes are not only minimal but frequent.
• Chemical intervention

This API Freshwater Test Kit is used to test for nitrate in my tank. It also measures 4 vital parameters.

Too Much Current

Strong currents are preferred by fish like rainbowfish, yoyo loach, and danios. Fish like bettas prefer to live in water that has low currents.

Strong currents can be very tiring for those who are in the second category. It takes a lot of energy to move against strong currents. They often rest at the bottom of the tank to get some much-needed rest.

Attach a sponge filter to reduce the flow of water from the filter. The current can be directed towards decorations and plants. The flow of water can be significantly reduced by breaking up the current.

Tank Is Too Small 

Fishkeepers underestimate the space requirements of fish and assume that they can live anywhere. This is especially true for small fish such as bettas or guppies who must be kept in a 2-gallon tank.

The fish can’t do much if the tank isn’t big enough. There is no space for exploration or exercise. Your fish will lose interest quickly in the things you are doing and simply lay down to waste time.

A larger tank is better than one that is smaller. It’s less temperamental and has plenty of space. To make things more interesting, you can add decorations such as plants and caves to the tank.

Small tanks also mean greater territorial aggression from its inhabitants. Sometimes, timid and subdued members are left with little to do but live in silence at the bottom.

Your Fish Is Stressed

Fish acting out of control is often due to stress. Fish are more intelligent than we think and can be complex. All of the above-mentioned reasons are stress-inducing for fish.

Stressed fish will often hide from the world and become reclusive. The tank’s bottom is a great place to hide, right?

You should ask your fish if they are constantly laying on the bottom. You could have fish being harassed by other tankmates, poor water conditions, or a bad diet. There are many reasons that could be the cause.

Worse, a stressed fish can cause immune compromises that lead to a variety of infections and diseases.

You can experiment until you find the right cause.

Your Fish is Resting

It’s not always alarming to see a fish on the bottom of a water tank. It’s possible that the fish is simply resting. Relaxing fish will often go to the bottom third of the tank, and stay there.

Pay attention to the fish. If the fish’s pelvic fins move gently and they are breathing normally, this means that the fish is taking a moment of relaxation.

This is often true for older fish. The average lifespan of an aquarium fish is between 3 and 5 years. They need to rest for a good portion of their lives, just like we do.

Even healthy fish need to take breaks from active swimming. You should provide them with plenty of rocks and cave decorations to rest in when they get tired.

It is difficult to establish the age of a fish if it has not been raised from its fry stage. Even though your fish was only born a month ago it could have been raised for several years at the breeder. If the fish looks older than it used to be, but is still healthy, this could indicate that the fish has become less healthy.

Your Fish is Sleeping

Many fish follow the same sleeping pattern as humans. Fish are active during the day and sleep at night. Fish need between 8-12 hours of sleep each night. If your fish lies on its stomach at the same time each day, or night, it is most likely sleeping or napping.

It can be hard to tell if a fish is snoring or not, as they don’t have eyes. Here are some signs that a fish might be sleeping: the slow movement of the tail and fins, gentle breathing, and an upright resting posture. Some fish, like bettas, sleep sideways.

Fish that aren’t getting enough sleep can often get caught up during the day.

Keep the light on a daily basis. Allow 8-10 hours of sunlight per day. Fish will become confused and stressed if the lights are on constantly.

Your Fish Is A Bottom Dweller

I am sorry if this is obvious but your fish could be a bottom feeder or bottom dweller. Fish are naturally inclined to live near the base for survival and hunting purposes.

Clown loaches, for example, lurk at the bottom of the gravel to attack snails, their natural prey. Kuhli loaches don’t just lie on the gravel, they also cover their whole worm-like bodies in it. Corydoras, on the other hand, love to hang out with friends and scavenge together in the base plants while timid zebrafish prefer to hide among them.

An interesting fact is that if your fish’s mouth is closer to the bottom than his head, it’s most likely a bottom feeder who spends a lot of time at the base.

Here’s a list of bottom-dwellers:

• Chinese Algae Eaters
• Kuhli loaches
• Corydoras catfish
• Otocinclus
• Plecstomus
• Synodontis catfish
• Zebra loach
• Twig catfish
• Bumblee goby
• Siamese alga eater

Frequently Asked Question

Why Is My Oscar Fish Laying On Side At Bottom Of Tank?

Oscars can grow to 10-12 inches in length. Lack of space is the main reason why an oscar will lay on its side at the bottom. Other causes, such as stress, aggression, or wrong parameters, could also be involved.

Why Is My Betta Fish Laying On Bottom Of Tank?

Although they have beautiful, long fins, betta fish aren’t used for anything other than eye candy. They can get tired easily if the current is too strong and have to lie on the bottom. Stress, illness, or an inhospitable environment could also be the reasons.

Why is my Molly Fish laying on the Bottom Of My Tank?

Mollies are peaceful, tiny fish. They are peaceful, small fish that can’t compete with dominant fish. This is why they often retreat to the bottom of the tank. However, they could also be suffering from foul water, cramped tanks, or a lack of space.

Final Words: Fish Laying On Bottom Of Tank?

Fishes are not as easy to understand as our dogs or cats. Fish have subtle ways that they communicate their feelings. And one way to communicate how they feel is by lying on the bottom of the tank.

If this does not happen often, don’t jump to conclusions. They are also known to sleep at the bottom.

If this behavior persists and your fish spends more time at the bottom than swimming, then you need to investigate the issue.

There could be many reasons, including toxic buildup, wrong temperature, stress, or diseases such as a swim bladder infection.

Do not panic, but try different ways to help your fish until you find the right cause. Have fun with fishkeeping!