Guppies are a popular type of pet fish to have because of their fun swimming behavior and colorful bodies.
There are 276 species of guppies, each with its own patterns and colors.
Guppies are quite small, and even the larger species only grow to about 2.4 inches.
Because they’re smaller, you can easily fit quite a few of them into the same tank.
They’re also friendly and feed on algae and mosquito larvae instead of bullying other fish.
Certain types of fish like to hang out in certain parts of a fish tank.
Guppies tend to congregate near the top of the tank, but they can swim anywhere.
If you notice that your guppies tend to linger towards the surface of the tank, then you may wonder if something is wrong.
Here are a few reasons your guppies might be swimming near the top of the tank.
Why Are My Guppies At The Top Of The Tank? (7 Potential Reasons)
1. Swim Bladder Syndrome
One of the more concerning reasons that your guppies may be at the top of the tank is that they’re suffering from swim bladder syndrome.
This refers to a situation in which something is affecting the fish’s ability to float or sink.
Every fish has a swim bladder that’s filled with gas.
The bladder helps the fish become buoyant.
It affects the fish’s ability to float around, sink, or even swim around.
There are a few symptoms that indicate your guppy might be suffering from swim bladder syndrome.
The first is if you notice that it is hanging around the top of the tank and unable to swim lower.
Watch the guppy for a time and see if it ever swims to a lower depth.
You should also see if it looks like it’s having problems swimming.
This is another sign that your guppy has swim bladder syndrome.
It may not be able to turn or move up and down as easily.
Bloated stomachs are a more obvious sign that your guppy has swim bladder syndrome.
This indicates that its bladder is full of gas, and the guppy is unable to release it.
A curved back is another physical sign of a swim bladder problem.
Finally, keep an eye on its appetite.
If it’s changed, then it could be because of a problem with its swim bladder.
There are many causes of swim bladder syndromes and the exact cause could be one or several of them.
Food or environmental changes could be causing the bladder to malfunction.
If the water’s temperature is too low, then it might also be affecting the guppy.
Colder temperatures make it so that the fish has to digest its food longer.
Finally, the existence of parasites or bacteria could be causing the syndrome.
How To Help Swim Bladder Syndrome
If your guppy is staying at the top of the tank because of a problem with its swim bladder, then there are a few ways that you can help.
The first way is to quit feeding for three days.
This solution is best for fish that have a noticeably distended belly.
The enlarged belly indicates that the fish is having problems digesting its food or that it ate too much.
The next step you can take is to monitor and change the water’s temperature.
Guppies are tropical fish and prefer warmer temperatures in their tanks.
If their water becomes too cold, then there’s a chance that they might be unable to digest their food properly.
This can lead to swim bladder problems.
Increase the temperature of the water a little to help them digest their food.
The next step to take is to feed them peas.
Peas are a great transitionary food for them before getting them back on their regular feed.
You need to remove the skin from the pea to make it easier for the fish to eat it.
You should also boil or microwave the pea to soften it up for them.
Finally, you should consider giving your guppy antibiotics.
If you suspect that the bladder problem is a result of parasites or bacteria, then antibiotics can help clear the body of the problem.
You’ll need to clean the tank thoroughly to ensure none of the other fish become sick.
With these steps taken, your guppy should be able to sink back down and swim throughout the tank instead of just at the top.
2. Poor Water Quality
Just like humans, fish also require a specific type of environment in which to thrive.
Unlike humans, fish aren’t able to adapt as easily to changes in their environment.
As such, they might start new behavioral patterns like swimming at the top of the tank to survive or to indicate their stress.
Several factors can make the water quality in your tank poor.
The first is temperature.
Since guppies come from tropical waters, they need warmer temperatures than other types of fish.
That’s why it’s important to know where the different breeds of fish come from if you plan on mixing them.
Mixing tropical fish with fish that come from the Atlantic Ocean or rivers in the frigid north isn’t ideal.
They’re going to require two different types of environments.
For guppies, the best temperature is between 74 degrees and 82 degrees Fahrenheit.
In most instances, you’ll need a water heater to keep the water at that temperature.
If the water becomes too cold, then they’re unable to move as well or digest their food.
This can result in them hanging around at the top of the tank.
Another factor that impacts the quality of the water is the pH.
Like plants, fish require a specific range of pH levels to stay healthy.
If the pH is too high or too low, then it makes it difficult for them to breathe.
Guppies require a pH between 5 and 7.
One of the biggest dangers facing guppy populations is water pollution.
By keeping the water clear and at the right pH, your guppies can breathe easier and swim easier.
How To Fix The Water Environment For Your Guppies
There are a few easy fixes you can do to make your tank suitable for your guppies.
The first is to buy a water heater.
There are tons of different water heaters on the market for fish tanks.
Some are more advanced than others.
If you want to save money, then you can buy a basic heater that just keeps the water warm.
The more advanced heaters are more accurate and tend to do a better job of keeping the tank at the best possible temperature for the fish.
Have a separate thermometer in the water, too.
This will give you a second reading of the water’s temperature which can help you if your heater ends up malfunctioning and giving you a false reading.
With constant monitoring, you can ensure your water’s temperature is at the exact level that guppies need.
Another step you can take is to invest in a high-quality filter.
The filter can help clear out the poor water and remove some of the properties that are affecting the pH.
That said, there’s nothing better than frequent tank cleanings, too.
Keeping the tank thoroughly clean will help the pH stay at its optimal level longer.
You’ll need regular fish-friendly acid and base solutions that can change the pH of the water as needed.
Understanding how to use those solutions and the quantity you need will ensure you keep the pH within the correct range.
3. High Ammonia Levels
Ammonia and nitrates are toxic to fish and guppies are no exception.
Ammonia builds in tanks in a few different ways.
The first is food that isn’t eaten.
As the food decomposes in the water, it releases ammonia.
Fish also release ammonia through the water as a waste product.
Ammonia is toxic to guppies because it impedes their ability to breathe.
It also breaks down their organs and causes stress to their gills, which makes it difficult for them to function.
Your guppy might be at the top of the tank because they’re having problems breathing or because there’s too much ammonia in the rest of the tank.
Ammonia can also grow in a larger concentration when the pH decreases or increases too much.
The same goes for sudden temperature changes.
If you notice that your guppy remains at the top of the tank, then it could be because of the presence of ammonia or nitrite in your tank.
How To Remove Ammonia From Your Tank
The good news is that it’s relatively simple to keep your tank ammonia-free.
You can buy kits at most pet stores that test for ammonia levels.
It’s important to note that most kits don’t test for the different types of ammonia in the tank.
They just let you know how much ammonia it’s detecting in the water.
There are two different types of ammonia, however.
Unionized ammonia is the type that’s toxic to fish.
Ionized ammonia isn’t as harmful, but it can start to harm them in large quantities.
The best way to remove ammonia from the tank regularly is with a biofilter.
The filter uses a certain type of bacteria that transforms ammonia into nitrite.
The problem with nitrite is that it is also toxic to fish.
This is why the biofilter also uses another type of bacteria that transforms nitrite into nitrate.
Nitrate is not toxic to fish except in large quantities.
One of the first things you should do when deciding to own fish is to ensure you have a high-quality biofilter.
This will keep ammonia from accumulating within the tank and harming your guppies.
Then you need to clean the filter and tank regularly.
This ensures that any lingering ammonia and nitrate are also removed.
Finally, you want to remove any leftover food that isn’t eaten from the tank.
By doing so, you can prevent it from decomposing into ammonia.
Taking these steps can help your guppies stay healthy and encourage them to swim throughout the tank instead of remaining at the surface.
4. Oxygen Deficiency
Another cause for concern that might indicate why your guppies are at the top of the tank is oxygen deficiency.
Fish require oxygen to breathe just like humans.
They get their oxygen by passing water through their gills.
The gills separate the oxygen from the rest of the water.
When something happens that makes it difficult for the guppies to separate oxygen from the water, then they start to suffocate.
As a result, they swim to the surface to gulp in the air instead.
There are a few reasons your guppies might be facing an oxygen deficiency.
One of the biggest causes is stagnant water.
When water is stagnant, it means that there isn’t any movement.
This is a problem because movement is how water gets its oxygen.
It’s also why the water at the bottom of the tank has less oxygen than water at the top of the tank.
There’s little movement at the bottom of the tank.
The size of the tank may also be too small for the number of fish inside it.
If there are too many fish in a small tank, then they’re all competing for oxygen.
This might lead those who are unable to get enough oxygen to swim to the top to get some from the surface.
How To Add More Oxygen To Your Fish Tank
There are a few ways that you can help ensure your guppies get enough oxygen.
The first is to install a filter that cycles water.
This helps push water through the tank and keep it moving.
Since the water is moving, it’s generating oxygen.
Another thing you can do is to buy air stones.
These are special stones that form bubbles and release oxygen.
They sink to the bottom of the tank and help generate a bit more oxygen down there for guppies to use.
Finally, you can also introduce real plants into the water.
Plants are a great way to help bring life and sanitation to your tank.
They can remove carbon dioxide, which the fish exhale, from the water and transform it into oxygen instead.
By making sure the filter is working and that there’s plenty of movement in the water, your guppies will have plenty of oxygen to use.
As a result, they’ll be more likely to swim throughout the tank instead of hanging around at the top all the time.
Fish don’t do well in stressful situations.
Guppies have a few stressors that might cause them to swim towards the top of the tank.
Crowded tanks are one of the biggest factors.
If the tank is too large, then it could be impacting everything from oxygen competition to food.
This can stress a guppy out and cause it to swim higher to escape the chaos.
Another big factor of stress is other tankmates who are bullies.
Some types of fish do not play well with others.
They’re competitive and may even kill other fish to ensure their own survival.
Guppies are friendly and don’t do well protecting themselves.
They’re school fish, which means they’re used to swimming with a pack of fish for their safety to deal with predators and bullies.
In a tank, they’re unable to rely on large numbers.
As such, if they’re experiencing a bullying fish mate, then they might hang out near the top of the tank where the bully leaves them alone.
How To Decrease Stress For Your Guppies
Helping your guppies decrease their stress is also easy.
Take into consideration the size of your tank and the number of fish you have in it.
If there are too many fish, then consider buying another tank and separating them.
You can also sometimes connect the two tanks.
This allows the fish to easily pass from one tank to the next when one is feeling a bit too crowded.
When it comes to bullies, you should consider separating that fish and giving it its own tank.
You can avoid some heartbreaking moments by keeping each fish in its own area.
Sometimes your guppy may be at the top of the tank for more innocent and simple reasons.
Over time, guppies will come to learn that they get fed at the surface of the water.
In anticipation of the food, they might swim near the top.
They might also do this when they’re feeling hungry.
They may believe that if they swim at the top of the tank, the food will appear.
If your guppy is at the top of the tank and everything else checks out, then it could be because it’s looking for food.
7. Top Swimmers
Fish are sometimes classified according to the type of depth that they like swimming in.
Guppies tend to be top swimmers.
This means that they spend most of their time swimming near the top of the tank.
They might also sometimes swim towards the bottom, but by and large, they prefer to be at the top.
That said, if your guppy is swimming at the very surface of the water, then that might indicate one of the problems listed above.
Otherwise, there’s a good chance that your guppy just enjoys swimming near the top of the tank.
Guppies are a popular fish that are prone to some of the same problems that all fish share.
These problems can sometimes cause them to swim to the top of the tank to alleviate them.
Other times, the guppy may just be hungry or have a preference for swimming at that particular depth in your tank.
By checking your water’s temperature, quality, and the ammonia levels of your tank, you can ensure your guppies remain healthy.