How Many Cory Catfish In A 10-Gallon Tank?

While keeping more than 4 cory catfish in a 10-gallon tank is not recommended, it is also generally advised to keep no less than 5 – 7 cory catfish together, as they prefer larger groups. Corys come in different species, with each being a different size, and some corys are too big for a 10-gallon tank.

When it comes to corys and tank sizes, a lot will have to do with the type of cory you wish to opt for; for some species, a 10-gallon tank is the minimum tank size, while for others, it is not even an option being too small. We will look at all you need to know about cory catfish, which species, and how many can be kept in a 10-gallon tank.

How Many Cory Catfish In A 10-Gallon Tank?

The number of cory catfish that can be kept in a 10-gallon tank is based on the size of the fish. With so many different cory varieties, the number of corys that can be kept in a 10-gallon tank will depend on species and size.

Because corys are social fish and do best when in a larger group, most tropical fish enthusiasts will recommend at least 5 corys per tank, but the more, the better. The problem is that smaller tanks like a 10-gallon tank do not allow for this many fish, particularly if the fish are of the larger cory catfish species.

10-gallon tanks can generally handle 4 cory catfish, but this will depend on the type of cory catfish you opt for. We will look at how tank size vs. fish numbers are calculated for cory catfish and which cory catfish can be kept within a 10-gallon tank while still enjoying the best quality of life.

Albino Cory Catfish on Sand

How To Calculate The Number Of Cory Catfish For Tank Size

Fish can get unhappy and unhealthy; this can often have to do with their tank size, as small tanks do not allow sufficient exercise for space or stimulation. Because of this, tank size will depend on the species and how the species lives.

Cory catfish are a gregarious species; they like to live in large groups and have been found to thrive when they are allowed to do so. While one can keep 1 or 2 cory catfish, it would be cruel, much like keeping a goldfish in a small bowl. How do we work out how many corys can fit in a 10-gallon tank and if it will be big enough for the fish to be happy?

It’s quite simple; there is a simple fish-keeping rule where you apply 1 gallon to every 1 inch of fish. So if you have a 10-gallon tank and 1-inch fish, you can safely keep 10 fish. The rule needs to be based on fully grown fish.

With cory catfish, taking two of the popular cory catfish species as examples, the largest cory catfish (emerald cory catfish) grows to 3 inches. In contrast, the smallest of the 7 ( pygmy cory catfish) grows to a maximum of 1 inch.

Doing the math, while one can fit 3 emerald cory catfish in a 10-gallon tank, they won’t be very happy due to how few of them there will be. Whereas with the pygmy cory catfish, a 10-gallon tank will comfortably fit 10 cory catfish, making it ideal.

Best Cory Catfish For A 10-Gallon Tank

So now that we know how to work out how many cory catfish we can fit in a 10-gallon tank, let’s see which cory catfish will fit in the tank with a suitably sized school. We have already determined that the emerald cory catfish is not suitable for a 10-gallon tank as they are too large to comfortably fit more than 5 fish.

On the other hand, the pygmy cory catfish we have seen will easily be kept in a-10 gallon tank.

We shall look at 5 more common varieties:

  • Albino cory catfish
  • Dwarf cory catfish
  • Three-stripe cory catfish
  • Bronze cory catfish
  • Julli cory catfish

The albino cory catfish can grow to the maximum size of 2 to 2.5 inches, meaning that one can only keep 3 or 4 at the most in a 10-gallon tank, which is not enough fish for a social species.

The dwarf cory catfish can only grow from 1 to 1.4 inches, so it is possible for a 10-gallon tank as 5 to 6 fish may be kept. Three stripe cory catfish can grow up to 2.5 inches, which will only allow for 3 to 4 fish in a 10-gallon tank which is just too few for the quality of life for the fish.

The bronze cory catfish can grow from 2.5 to 2.75 inches making it too big for more than 3 fish in a 10-gallon tank. Lastly, the julli cory catfish is another catfish that does not meet the size requirements for more than 5 fish as it grows to 2 to 2.5 inches, only allowing 4 fish in a 10-gallon tank.

Cory Catfish That is Suitable For A 10-Gallon Tank.

As there are over 160 species of cory catfish, one can make life easy by saying that any species that grow to less than 2 inches will be able to live happily in a 10-gallon tank. All species with a maximum length over 2 inches will not be suitable.

Of the more common cory catfish species, the two that are compatible with a 10-gallon tank are the dwarf cory catfish and the pygmy cory catfish. Both these cory species allow for more than 5 fish while still fitting the tank for size.

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One can fit 5 to 10 cory catfish in a 10-gallon tank, provided the species is a small one that does not grow to more than 2 inches, as cory catfish need to live in a group of at least five of the same species for the best quality of life. Some people keep 4 to 6 larger species of cory catfish in a 10-gallon tank, but this is not advised for the sake of the fish’s best interests.