Cory catfish are one of the few fish that can reliably live with betta fish. With their docile nature, Cory catfish don’t aggravate the notorious prey drive that makes bettas such difficult tank mates.
Cory catfish, also known as Corydoras, are one of the most popular fish in the aquarium hobby, especially for community tanks. These little catfish come in a variety of colors and patterns, feed almost exclusively on the bottom of the tank, and are never aggressive.
Bettas, on the other hand, are beautiful fish that are usually kept solitary. They are hunters with a high prey drive that are fiercely territorial, rejecting all but the calmest of tank mates.
Why Are Cory Catfish Good Tank Mates For Bettas?
Betta fish are gorgeous, colorful fish that just so happen to be some of the most violent around. They will attack and kill any other fish or tank mate they see as competition.
Many betta keepers suggest keeping bettas by themselves, but it may surprise you to know that there are a few fish that make ideal tank mates for these deadly beauties!
Because they occupy a different water column, feed on different foods, are more dully colored, and are incredibly peaceful, Cory catfish are one of the best choices of tank mates for bettas.
As predators that primarily hunt for their food, bettas live in the top water column. (Notice the slightly upturned mouths designed for grabbing food from the surface, as opposed to the downturned mouths on corydoras who scavenge food from the bottom.)
Bettas are also labyrinth fish and need to occasionally breathe air from the surface because of their unique labyrinth organ, meaning it’s important for them to remain near the surface of the water.
On the other hand, Corydoras are bottom feeders that don’t hunt, enjoy both vegetation and small sand-dwelling invertebrates, and scavenge for their food by digging in the sand and sifting it through their gills to find tasty morsels. Corys rarely enter the top water column, preferring to swim and rest along the bottom of the tank.
Since Cory catfish and bettas live in different parts of the aquarium, they don’t come into contact with one another often and don’t compete for food.
Simply put, bettas seek live food and subsist by hunting living prey while Corydoras get their nutrients by sifting through their substrate and eating the plant matter and small invertebrates they find, like nematodes and daphnia.
When feeding your community tank, you’ll notice that betta food floats on the water and Corydora pellets and wafers sink. Since they don’t compete for food, Cory catfish and bettas get along swimmingly.
Bettas, because of their super aggressive nature, will try to kill anything they perceive as a threat or mistake for another betta. Flashy fish like fancy guppies and gouramis will quickly draw the ire of the angry betta.
Cory catfish tend to be muted colors, and don’t have the long, flowing fins that bettas detest, meaning bettas don’t feel threatened by their presence and will accept them as tank mates.
Do Bettas Ever Attack Corydoras?
While Corydoras usually make lovely tank mates for bettas, experienced betta owners know some bettas are so violent and ill-tempered that they won’t tolerate any tank mates at all, even the peaceful Corydora.
When combining these two fish, observe your betta closely, and if there is any sign of the betta chasing or harming the catfish, separate them immediately.Some bettas are, unfortunately, destined to live alone forever.
How to Introduce Corydoras to Betta Tanks
The best way to introduce corydoras to a betta tank is to remove the betta from the tank (to a small bowl or something – just temporarily) and then add the corydoras.
While your betta is outside of the aquarium, add some new decorations or move some things around. Then, add in your corydoras and give them a few minutes to an hour or to so they can settle in.
Once your corydoras have settled in and had a chance to find their hiding spots, add your betta back into the aquarium.
This will make it less likely for your betta to have his territory mapped out and decide that your corydoras are invaders.
You’ll want to make sure your aquarium is big enough for your corydoras – at least 10 gallons if you’re going to have pygmy corydoras or 20 gallons for full sized ones.
Do Cory Catfish Eat Betta Poop?
Cory catfish are bottom feeders and are often known as ‘cleaning crew’ fish, along with kuhli loaches and plecos, but they don’t eat betta poop. In fact, there are no fish that seek out betta poop as a part of their diet.
The myth of Corydoras eating betta poop may stem from the way that Corydoras eat.
These little catfish love to enthusiastically dig through the sand to find their food, and in the process, can bury betta poop that has fallen to the substrate, making it appear that the Cory catfish has eaten the poop.
Can Pygmy Cory Catfish Live With Betta?
Pygmy Cory catfish, just like normal Cory catfish, make great tank mates for bettas.
One of the more unique subsets of Cory catfish is the Pygmy Cory catfish. The regular-sized Cory catfish reach 2.5 inches long, but the pygmy variety is less than 1 inch long! Being so diminutive, Pygmy Corydoras are perfect for smaller betta tanks.
Pygmy Corys might be even better suited to sharing a take with a betta than their larger counterparts. They are shyer and less brazen than normal Corys, and with their small stature, they almost never seem like competition to bettas.
That having been said, habrosus corydoras are the best suited species of pygmy corydoras for living with betta, because they tend to be a bit more mellow and hang around the bottom a bit more.
You might also see them called Salt And Pepper Pygmy Corydoras.
In general, cory catfish make great companions for betta. Their peaceful nature combined with the fact they primarily hang out at the bottom of the aquarium make bettas less likely to attack them than most other species.
In small tanks, the pygmy corydora known as C. Habrosus is the best type of corydora to live with bettas.
That’s not to say all betta will get along with all corydoras. Betta are incredibly tempermental, and some bettas will just decide they don’t like anything else in their aquarium.
Because of this, you’ll want to keep an eye on things, and maybe remove your betta while you add your corydoras to your aquarium.