Do Cory Catfish Eat Algae?

By Algal Web

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If your tank or pond is overrun with algae then you might be tempted to algae-eating fish species. The right fish species can reduce rapid algae growth and many bottom-feeding fish species are also helpful for clearing other messes and particles from your tank. 

Lots of people include corydoras catfish in their aquariums because the peaceful fish species is extremely attractive and they are dolce in temperament which makes them unlikely to harm the other fish species in your community tank. 

But one of the biggest questions you need to ask before you buy this type of bottom feeder is; do cory catfish eat algae?

In this guide, we find out what this catfish prefers to eat so you can see whether it will be a helpful addition to controlling algae or not. 

Cory Catfish Species Summary

Cory catfish or corydoras is a freshwater fish species that prefer to hang around at the bottom of ponds, lakes, and rivers. They are mostly located in smaller streams and are extremely popular in fish tanks because of their unique appearance. 

The different species of corydoras can vary a lot in their appearance or color but their distinctive body warmer and fin positioning makes them easy to identify. This fish has a lot of sharp, and often venomous spines that they use to ward off predators. 

Here is a quick look at some of the characteristics of this ornamental species. 


Scientific Name: Corydoras Melanotaenia

Food Sources: Algae wafers, fish flakes, blood worms, shrimp pellet, bottom feeder tablets

Avg. Fish Size: 1 – 2.5 Inches

Life Expectancy: 5 Years

Pond Size: 30-Gallon tank

Water Conditions:  74 – 80 Degrees F,  7.0 – 8.0 pH level

Temperament: Peaceful, non-aggressive, and shy

Do Cory Catfish Eat Algae?

There are quite a few ornamental corydoras species that are sure to make your aquarium look a lot more appealing. But if you are looking for a fish species that is going to control algae then it might be better to look towards other types of bottom feeders.

This fish species do not feed on algae. People often mistake corydoras catfish for algae eaters because they sometimes nibble at algae growths but they hardly ever consume this type of growth. They won’t eat any algae that might be growing on your tank glass, on the gravel, rocks, or on your decorations and they also don’t eat green algae that might be floating around in the water.

The only algae these species do eat occasionally is a sinking algae wafer.  

But despite that they do not eat any algae, they can still be very helpful for keeping your tank clean from other waste products. 

What Do Corydora Catfish Eat?

This fish species can help clear all sorts of particles from your tank floor and surfaces. They are efficient bottom feeders and can suck food particles out of gravel or sand on the bottom of a tank. This fish species can improve the water quality and ecosystem of your tank while reducing the frequency of tank cleans you might need. 

Here is a quick look at the types of food or messes this catfish is happy to clear out of your tank.

Do Corydoras Catfish Help Clean the Tank?

Corydoras certainly can help keep your tank nice and clean. They eat a huge variety of food particles off your tank floor and will keep these particles from decomposing and rotting. They prevent gunk deposits on your tank floor and can keep your freshwater tank clear and odor-free. 

They are also highly effective for tank cleaning since you can add a small school of corydoras to your tank without risking the other fish. They are not the most social fish species and prefer to hide away but they are dolce and friendly. Schools of corydoras get along well and they are not very likely to lash out at the other tank mates. 

What Catfish Eat Algae?

Cory catfish can be combined with algae eaters to create a tank that is both algae and fish waste-free. With their friendly temperament, they can be introduced in just about any tank community along with any type of algae-eating fish species. Here is a quick look at some of the best algae eaters to add to your tank.

Twig catfish

These fish species need about 12 gallons of water per pair and they are a great addition to your tank because they love to feed on algae. Twig catfish are, however, vulnerable to some other tank species like barbs and cichlids who might harm them. 

Bristlenose plecos

Bristlenose plecos are hardy, easy to care for and there are quite a few varieties in different colors available. They love to feed on algae but they are quite large with an adult size of about 5 inches. They can be a very good tank mate in larger tanks of over 25-gallons. 

Otocinclus catfish

Otocinclus catfish or dwarf suckers are not very easy to breed but they are terrific algae eaters. They have a calm but shy temperament and can easily be combined with your cory catfish to keep the tank nice and clean.


Mollies are a very popular aquatic fish species because they are fast swimmers that come in a huge variety of bright colors. The common molly love to feed on all sorts of aquatic plants and they are especially fond of algae. They can however be mildly aggressive but are not likely to harm your catfish since they prefer the upper part of the tank. 

Siamese algae eater

Siamese algae eaters are some of the most effective algae-eating fish species but they are not to combine with cory catfish. This fish species can be very territorial and will harm other bottom feeders. They can help control algae growth but should be kept apart from other bottom feeders. 

Siamese Flying Fox

Siamese flying foxes are also bottom-dwelling algae eaters that will help keep your tank nice and clear. They are fond of green algae and are quite social. They can be kept in schools and combined with other tank mates but they can sometimes become territorial as adults. 


Snails are not the most attractive aquatic animal but they are terrific for clearing algae from your tank. They don’t need a lot of room and won’t harm any other fish species in the tank. Most aquatic snails do breed quickly and this breeding rate can result in other messes in your tank. Rabbit snails won’t breed as often and grow slowly which makes them the best candidate for aquariums. 


Shrimp is a good option for small fish tanks. Cherry shrimp is an especially good species since it can function well in small water bodies and it is a very efficient algae eater. They are also great at getting algae cleared from hard-to-reach areas and this species can be included in community tanks with small fish species. 

Final Thoughts

So do cory catfish eat algae? Sadly no. But they can be combined with other algae eaters to create an aquarium or pond that stays cleaner for longer. This ornamental fish species is a useful cleaning companion to include in your community tank but you might want to look at some of the other guides we have on AlgalWeb to find a good solution for controlling rapid algae growth in your tank or pond.

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