Do Cory Catfish Get Lonely? {Can They Be Kept Alone?}

Should cory catfish be kept in groups? Do cory catfish get lonely?

Do cory catfish get depressed? Are there any types of cory catfish that are more lively?

We have all these answers and more for you in this article on whether of not cory catfish get lonely.

Can Cory Catfish Get Lonely?

Yes. Cory catfish are:

  • peaceful
  • sensitive 
  • social

They can get lonely in small or overcrowded tanks. Various threats to their health can cause them stress which looks and feels like depression from loneliness.

Studies continue to validate that fish can get depressed and lonely. The information below will show that.

Is My Cory Catfish Lonely?

Cory catfish can be kept in large numbers. They do not depend on a school, but they like this option very much. Shoaling behavior is exhibited during:

  • times of nervousness
  • when they engage in tank cleanings
  • when hunting through the substrate

They enjoy the strength in numbers. A lonely catfish could be one that is:

  • without tankmates
  • bullied by other fish
  • less social 
  • less active
  • bloated often
  • showing signs of illness

How To Help A Lonely Cory Catfish

  1. Add more cory catfish if possible. 1 gallon could host 1 cory. They can mix and fit in with different types of cories. Some cories prefer their own kind. Consider adding more that match your particular cory catfish.
  2. Some tankmates could get aggressive and cause your cory to isolate itself from the group. Some cory catfish prefer isolation.
  3. Digestive issues like constant bloating or insufficient nutrients being absorbed will cause some cory catfish to retreat into a lonesome spot at the bottom of the tank.
  4. Check the gills for irritation and their fins for rot. If your cory catfish is eating well and the fins are alert, then try not to be very concerned about it yet.
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Why Is My Cory Sick?

Treatment for illnesses are varied and sometimes misunderstood. We may try to treat one condition when there was a different underlying problem that the medicine did not address.

Sometimes we overmedicate or jump to medicating before performing heavier water changes and making sure the nitrogen cycle is healthy and thorough.

An ill cory catfish that has recovered could still be displaying the effects from the medication that is causing it to act sluggish or downright lonely.

It will take time to show a full recovery and adding more nutrients through live or frozen food dipped in vitamin based solutions could help speed up the process as well.

Which Type of Cory Catfish Is More Active?

If you’re looking for active cory catfish, you may want to look into stocking your tank with the same type instead of mixing them up. Some cories feel more comfortable with their own species, but others are fine with the diversity.

The following types of cory catfish tend to be more active:

  • Sterbai
  • Panda
  • Julii
  • Aeneus (albino or bronze)

This doesn’t take into account that personalities vary regardless of type or breed. Some cory catfish are just going to disengage and chill out.

Make sure the water parameters are ideal for them and check to see if they’re eating all the food you’re offering. If not, change up the meals and see if that helps as well.

Is My Cory Catfish Grieving?

Cory catfish like to shoal in groups. They may also bond with one particular partner in the group for a while. They could seek shelter together or scrounge the substrate in unison. If one of these cory catfish is removed or dies, the other could feel depressed. They could:

  • sulk
  • act sluggish
  • refuse food
  • hide more than usual
  • stay or sleep in corners longer
  • become inactive

Check to see if this behavior persists longer than 5-7 days. If food is being refused, offer this cory catfish some brine shrimp or bloodworms to see if that helps. Add another potential partner to help fill that void if possible.

Is My Cory Sad Or Getting Old?

Sometimes we can confuse depression in our cory catfish with loneliness or aging. They are much more active when they are younger. A cory catfish is generally peaceful by nature. An active cory is concerned about:

  • mating
  • finding spaces to spawn
  • investigating its new environment
  • looking for food

The older a cory catfish gets, the more we have to accept that they are becoming sluggish by choice. The oldest cories in your group could slow down or isolate themselves.

You may have a fish that is used to its environment and getting plenty of food so there’s no need to display that active nature it used to.

What Can I Do To Liven Up My Cory Catfish?

We offer tips and suggestions that may not work for all cory catfish. We’re happy that some people and their cory catfish have been positively affected by some of this advice and we offer them for you as well:

  • Perform larger weekly water changes up to 50% per week for the next 3-4 weeks.
  • Keep as much beneficial bacteria in the filter’s media and only rinse it with tank water when cleaning.
  • Offer variety in their diet like bloodworms and algae wafers that sink to the bottom of the tank.
  • Cycle your tank fully for up to 8 weeks.
  • Add more cory catfish.
  • Look for symptoms of illness or parasites on their bodies, fins and gills.
  • Remove aggressive tankmates.
  • Corydoras are not as hardy as guppies. Consider your cory’s ideal water parameter levels first.
  • Get a water conditioner to remove ammonia.
  • Vacuum or siphon hose the substrate every week.


Cory catfish can get lonely, but they can also be inactive because they aren’t the most boisterous of fish. If too many active fish are around them, they may retreat further into isolation.

If your cory catfish has a good appetite and its fins are actively alert, then try not to be overly concerned for now.

Your cory catfish could use more company, but a tank large enough to prevent overcrowding and poor water conditions is most important.


We hope your cory catfish cheers up soon or enjoys the tranquility of existing peacefully at the bottom of your tank!

Brian Arial

Brian Arial has kept fish for leisure and worked with fish stores for most of his life. He enjoys writing and caring for aquariums and ponds.