Cory Catfish And Loaches: Everything You Need To Know

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Cory catfish and loaches are quite common species in home aquariums, mainly because they are excellent scavengers.

And yet, many aquarists are a little hesitant when it comes to these two species.

Some have no idea if they can share the same tank, while others just want to grow one of them, but have no idea which one to choose.

In this article, I will explain everything you need to know about these two questions. Let’s dive right into it.

Can Cory Catfish And Loaches Live Together?

Yes, cory catfish and loaches can live together.

When you consider the following factors, it becomes evident that cory catfish and loaches are compatible with one another:

1. Each Species Is Active At Different Times

People like loaches because the creatures are bottom dwellers. You can trust them to stay out of the way.

However, Cory catfish are the same. They also frequent the bottom. But loaches have one additional advantage; the species is nocturnal.^[1]

They spend the daytime sleeping or even hiding (depending on their temperament), only emerging to feed and explore after sundown.

You can coax loaches out of hiding during the day if you have sufficient foliage. But for the most part, they will leave the cory catfish alone during the daytime.

Cory catfish are not like conventional catfish. They are active during the day.^[2]

2. Both Enjoy Similar Water Parameters

Cory catfish and loaches will thrive under the same parameters.

Loaches require a temperature of 75 to 86 degrees, a pH of 5.5 to 7.8, and a hardness of 3 to 10dGH.

As you can see, loaches are hardy creatures that tolerate various environments.

Cory catfish are the same. They need temperatures of 72 to 78 degrees and a pH of 7.0 to 7.8. However, the parameters may change depending on the fish.

For instance, Barbatus Cory can survive in water as cold as 16 degrees C, which is perfect for tanks without heaters.

Identify a type of cory catfish whose requirements match the parameters in the loach aquarium.

Below is a table summarizing the water parameters for each of them, and the ones you should aim for in a tank that holds both species:

Parameter	Loaches	Corydoras	Loaches & Corydoras
Temperature	75-86° F (24-30° C)	72-78° F (22-26° C)	75-78° F (24-26° C)
pH	5.5-7.8	7.0-7.8	7.0-7.8
Hardness	3-10° GH	5-10° GH	5-10° GH

3. Corydoras And Loaches Are Peaceful

Cories and loaches are excellent tankmates because of their peaceful temperaments.

They don’t harass their neighbors or seek out conflicts unless another creature aggravates them.

Therefore, you can trust them to live side by side without antagonizing one another.

The loach’s nocturnal patterns are particularly advantageous because these creatures do not have to interact with one another.

What Is The Right Tank Size For Corys & Loaches?

The tank size is your biggest problem because it directly impacts fish behavior.

Abudusaimaiti Maierdiyali, Zhongqiu Li, Lin Wang, and Yunchao Luo proved as much when they explored the influence of tank size on zebrafish (Animals Journal).^[3]

They found that zebrafish in smaller tanks had less courage and poor stamina.

Giovanni Polverino, Thomas Mehner, Tommaso Ruberto, and George Staaks had a slightly different take.

A study they published in volume 115 of ‘Animal Behavior’ noted that tank size was more likely to alter behavior in juvenile fish, especially where risk-taking was concerned.^[4]

But mature fish were more likely to repeat the behavior they adopted during the juvenile stage.

This is dangerous because loaches are larger than cory catfish. Consider the clown loach, which can grow to a size of 7.9-11.8 inches (20-30 cm).^[5]

You need 100 gallons or more to keep a group of clown loaches happy. And if you can afford a large tank, these creatures will co-exist peacefully, even during mealtimes.

But if the tank is small, the loaches may develop an aggressive streak that compels them to attack their cory catfish neighbors.

A group of clown loaches will need at least 100 gallons, and they should indeed be in groups of five to six.

Cory catfish don’t exceed 4 inches and can handle a 20-gallon tank, which is why it’s the loaches that determine the size of the tank if you want to keep both species.

However, during their breeding season, cory catfish can lay eggs every seven days. At this time, they will need more than 20 gallons.

What Types Of Loaches Can Live With Cory Catfish?

The key to a peaceful aquatic environment is ample foliage, abundant food, and a large tank. Although, the type of loach is just as important.

The following loaches will co-exist peacefully with cory catfish:

Kuhli Loaches – peaceful bottom dwellers that are best kept in groups of 3-6.

Clown Loaches – Beautiful, and only dangerous in small tanks because they can grow to 12 inches (about 30 cm).

Zebra Loaches – Hardy creatures with a mouth suited to eating invertebrates.

Yoyo Loaches – Cheaper than clown loaches and suited to large tanks but not appropriate neighbors for invertebrates.

Dojo Loaches – Colorful, excitable, and suited to unheated aquariums.

Horsehead Loaches – A nocturnal creature that only comes out at night to look for food.

Rosy Loaches – Tiny fish (1-1.25 inches) that eat equally tiny foods.

Weather Loaches – Fast-moving fish that react to weather changes. They burrow into the substrate in search of invertebrates and leftovers.

Polka Dot Loaches – Smaller and more peaceful than the yoyo loach, but you should keep them in groups of 10.

Bitterling Loaches – Small (2 inches), peaceful, and available in silver and black patterns.

Golden Loaches – Grows to six inches and co-exists with smaller species.

Cory Catfish vs. Loaches: Which One Cleans Best?

This question is fascinating because people don’t necessarily treat cory catfish and loaches as tank cleaners.

The creatures are bottom dwellers, meaning they eat food at the bottom. But you can’t trust your aquarium’s maintenance to either species.

Additionally, it is dangerous to add a fish to your aquarium for the express purpose of cleaning your tank because you may wreak havoc on the aquatic environment.

This happens all the time in the wild.

Consider the example of a South American endemic fish, a tank cleaner that a team from the State Planning Commission’s Land Use Research Board has identified as a menace to native species in Tamil Nadu.^[6]

Adding loaches and cory catfish to clean an aquarium could do more harm than good.

However, if you can only house one of these two species and you want to know which one is more advantageous, the answer is pretty simple:

Cory catfish and loaches are equally effective at foraging for leftovers at the bottom.

Many people flock to loaches because they are curious and playful. They are more likely to dig into the substrate in search of food. On the other hand, cory catfish are awake all day, which is also beneficial.

The results you record will depend on the temperament of the loaches and cory catfish in your aquarium.

Some loaches are incredibly lazy and ineffective where aquarium cleaning is concerned. The same goes for corydoras.

That is why many fish owners grow other types of scavengers, including shrimp. For example, cory catfish and ghost shrimp go great together.

How Many Cory Catfish And Loaches Should I Get?

Cory catfish are shoaling fish that require six or more of their kind to thrive.^[7] Otherwise, they won’t feel safe.

Loaches are in a similar boat. You should keep three or more in a group. But some loaches are so large you need 100 gallons of water or more to house multiple loaches.

This is why many aquarists prefer to keep loaches in a separate tank. Adding another species to the equation compels you to increase the size of the aquarium.

Cory Catfish vs. Loaches: What’s The Final Verdict?

There is no definitive answer to this question, as both species are great and relatively peaceful. The main factor here is the size of your tank.

If you have 100 gallons or more, you can comfortably pick a group of loaches. You can even keep them with corydoras, as I explained before.

Many aquarists will go with loaches as they are a bit more exciting and interesting. But if your tank is small, you should avoid them at all costs.

You should also consider your goal. If you want to get rid of algae, both species will do a great job. But they are unlikely to fight other pests such as snails.

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Conclusions

If you want to grow both loaches and corydoras, nothing will stop you except the size of your tank, which should be at least 100 gallons (for the loaches).

Apart from that, both species are equally peaceful and share similar water parameters. Also, as opposed to corydoras, loaches are active during the night.

However, if your goal is to find a scavenger to keep your tank clean, you should know that you cannot rely solely on these two species.

Routine aquarium maintenance is a crucial step any aquarist should implement, regardless of its aquarium inhabitants.

References

https://www.aquariumcoop.com/blogs/aquarium/cory-catfish-care-guide