Caring for plecos in your home aquarium has the potential to be so satisfying. These are great fish that are generally pretty hardy.
Many types of plecos are beginner-friendly. That doesn’t mean that things can’t go wrong, though.
If you notice that your pleco is just floating in the water, you’re likely going to be quite worried. When the fish isn’t dead but it’s just floating it’s going to be confusing.
What is going on with the fish? Keep reading to get to the bottom of this situation.
Check that it’s Alive First
It’s worth mentioning that plecos might float when they’re dead. Are you sure that your fish is still alive?
Observe the fish and try to spot whether its gills are moving at all. If they aren’t, then the fish might very well be dead.
If you attempt to touch the fish, will it start moving? When you poke a fish and get no response, that’s a sure sign that it’s dead.
Sadly, it could be that the fish simply died for one reason or another. If you’re sure that the fish is still alive, there are other things to look into.
1 – Stress Issues
It’s possible that stress could be causing the fish to float. Plecos might do strange things when they’re feeling stressed.
This could be taken as a sign that something isn’t right in the tank. Perhaps the water parameters or off or the water might be dirty in some way.
It’ll be wise to check the water to see where everything is at. Remember that you should be regularly testing the water to keep the parameters in check.
Address any problems in the tank and see if you can get the fish to start acting normal again. Hopefully, it’s not going to be a big deal and all will be well.
2 – Is the Pleco Simply Looking for Food?
Plecos are omnivores that scavenge for food. While they usually hang out at the bottom of the tank scrounging for food, it isn’t impossible that a fish would float around to look for something to eat.
Perhaps the pleco fish didn’t get enough to eat. Are you feeding the fish properly?
Some novices who are just getting used to taking care of fish make mistakes with plecos. You might have bought plecos due to hearing that they eat algae in fish tanks.
While many plecos do like to eat algae, not all of them will do this. Plus, plecos that do eat algae will need more to survive than just algae.
You need to feed these fish a balanced diet if you wish for them to stay healthy in your aquarium. Thus, it’s important to put some effort into feeding them.
People often feed plecos sinking nutritional pellets, algae wafers, bloodworms, shrimp, and even certain types of vegetation. They eat many different types of food, but you’re supposed to give them a properly balanced diet to help them thrive.
3 – Low Oxygen Levels
Have you checked the oxygen levels in the tank recently? There have been situations where plecos will start floating near the surface of the tank when the oxygen levels aren’t sufficient.
These fish need to be kept in water that has a high oxygen level. If the fish tank doesn’t have a good filter, then the fish aren’t going to be able to survive.
Seeing your fish floating near the surface could be a sign that you need to fix things. Your fish could die if you aren’t able to turn things around.
Oxygen levels will become lower in the tank due to high nitrate levels. Nitrate levels become elevated when you don’t do a good job cleaning the fish tank.
Regular tank maintenance is an important part of caring for your fish. Remember that you’re supposed to clean the tank regularly to prevent the water from getting too dirty.
Water changes are just as important as cleaning the tank. You absolutely must change fifteen percent of the water each week.
Some people get away with doing water changes on a biweekly basis, but it’s better to do weekly water changes. Get in the habit of doing tank maintenance each week and you’ll have an easier time keeping your fish healthy.
Do your best to solve any issues in the tank that are making it hard for the fish to breathe. This should help the fish to return to normal activity so long as it’s not too late.
4 – Overcrowding
Overcrowding could be to blame for the pleco fish just floating around. This is likely related to low oxygen levels as mentioned above.
When you try to cram too many fish into a fish tank, it’s going to create a number of problems. Simply put, more fish will produce more fish poop.
If you have more fish than you should in the tank, the water is going to get dirty too fast. It’ll be far trickier to keep up with cleaning the tank, and the fish will suffer because of it.
Since plecos are sensitive to lower oxygen levels in the tank, you might notice them experiencing negative effects first. Elevated nitrate levels due to the presence of too much fish poop will be tough for them to bear.
Remember that you’re supposed to give each fish in the tank enough space. Plecos are sort of big fish, and they require room to be able to live comfortably.
Even smaller plecos will need enough space to thrive. You should never try to cram too many fish in a tiny fish tank.
Plecos can be great community tank fish, but you need to buy an aquarium that is large enough to house them. Many plecos can only be kept in 100-gallon fish tanks or even larger ones than that.
5 – Bloating
Sometimes plecos will float because they’re bloated. Bloating can have a negative impact on the swim bladder.
Fish need to be able to use their swim bladders so that they can swim normally. A bloated belly might press against the swim bladder and keep the fish from being able to swim around.
Look at the fish and try to examine its belly. Does the belly appear to be bloated?
If you notice that the fish looks rounder than usual, it’s likely that the fish has become bloated. It might simply be constipated due to eating too much food.
Feeding plecos too much can cause bloating. The fish can become constipated when their digestive systems back up.
Other things can cause fish to become bloated as well. For example, worms might cause fish to experience bloating issues.
To solve bloating and constipation problems, it’s good to try to feed plecos frozen peas. Peel the skin off of the peas and microwave them for thirty seconds.
The fish should eat the peas and it’ll make it poop a lot. The pooping will clear the fish up and it’ll no longer be constipated.
6 – Swim Bladder Disease
As you might expect, swim bladder disease can cause fish to float around aimlessly. You might even notice your pleco trying to swim upside down.
This isn’t a problem that you want to ignore. Some swim bladder issues can cause fish to suffer in various ways.
Of course, it’s harder for the fish to get around when they have swim bladder problems. They might not even be able to eat properly.
Swim bladder disease can be caused by so many things. You already learned about bloating and constipation above.
It’s also possible for plecos to experience swim bladder issues due to becoming infected. A bacterial infection can wind up causing intestinal swelling that will lead to swim bladder disease.
In many cases, the only way to clear things up is to give the fish antibiotics. You’ll need to get rid of the medication so that the swim bladder issue can go back to normal.
Another possibility is that the pleco swallowed too much air. Plecos will sometimes swallow air when they feed at the surface of the water.
Gulping down too much air can make the fish experience bloating. The enlarged belly of the fish will push against the swim bladder and cause it to malfunction.
Trauma might cause swim bladder issues, too. If your pleco fish fights another fish, it might get injured in some way.
A physical injury could cause abdominal swelling. The swim bladder organ itself could also be injured directly by slamming into an object or getting attacked by another fish in the right spot.
There are even plecos that are born with swim bladder deformities. If your pleco fish is new to the tank, then you might have simply purchased a deformed fish.
7 – General Disease
You might be worried that the fish floating in the tank is a sign that it’s dying. This could very well be the case.
Sometimes fish will contract certain diseases that will cause them to act strange. Your pleco fish could simply be sick and it is now floating around despite not being dead yet.
It’s hard to say what disease the fish might have. The fish could have a severe infection or it could be dealing with a parasite.
You’ll want to look out for other symptoms to try to get an idea of what is happening. If you can determine what’s wrong with the fish, it might be possible to treat it and get it back to being healthy.
The best thing to do is likely to enlist the help of an exotic veterinarian. A vet will be able to diagnose the fish and tell you what is going on.
If you don’t wish to pay for the vet to help, then you can attempt to determine what is wrong on your own. You’ll have to pay close attention and try to figure out what’s happening.
The fish might get back to normal after receiving treatment for a disease. Or it could be too late for the fish and it will simply wind up dying.
How to Help the Plecos
Helping the plecos is really going to be about caring for them properly. Seeing a fish floating around in the water isn’t normal.
Under normal circumstances, plecos shouldn’t be doing this. It’s definitely an indication that something is wrong.
To keep issues like this from occurring in the future, you should do a better job of maintaining the tank. Keeping the fish tank clean and doing regular water changes will help.
You’ll also want to test the water regularly using a pH balance testing kit. This will alert you when something is wrong so that you can make changes before things get too bad.
Keeping the fish healthy will be easier when you feed them properly, too. Don’t make the mistake of thinking that plecos can live by just eating algae in the tank.
Depending on which plecos you own, the fish might not even like algae. Feed the fish recommended foods that will meet their nutritional needs.
Remember not to feed the fish too much, though. Overfeeding plecos can lead to constipation issues.
When a fish becomes constipated, it can experience swim bladder problems. This might cause it to swim upside down or float in the water aimlessly.
Knowing what to look out for should help you to care for the fish better. You’ll be able to keep the plecos safe by being proactive.
Learning about why plecos might float in the tank should help you figure out what to do. If you’re sure that the fish isn’t dead, it’s most likely some type of swim bladder issue.
The fish might have eaten too much and become constipated. If that’s the case, you can feed it peas to get it to poop out the excess food and get back to normal.
Lots of things can cause fish to experience swim bladder issues. It could be related to some type of bacterial infection or even a physical injury.
Stress and poor water conditions can cause fish to start floating or otherwise act strangely. Keeping plecos in overcrowded fish tanks will also put them in danger.
When the oxygen levels in the tank are low, plecos might float near the surface. This happens when you don’t clean the tank enough and the nitrate levels get too high.
Do your best to monitor the conditions in the tank moving forward. You should be able to keep the plecos safe by taking the right steps with tank maintenance.
Jeff has always enjoyed having pets, but as a child, he was drawn to his family’s fish tank. Being able to maintain a small ecosystem and observe the behaviors and interactions in the underwater world peaked his interest early on and has kept him hooked until this day. On Avid Aquarist, Jeff shares everything he’s learned about helping aquatic life survive and thrive in a home aquarium.