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Cory Catfish vs. Otocinclus (Key Similarities and Differences)

Cory Catfish vs. Otocinclus (Key Similarities and Differences)

This post is written to the author's best knowledge and is not intended to be used in place of veterinary advice. In addtion, this post may contain affiliate links. As an Amazon Associate I earn from qualifying purchases.

Both cory catfish and otocinclus fish are considered to belong to the catfish family. If you’d like to buy some catfish for your aquarium, then you might be trying to decide between cory cats and otos.

They are similar in certain ways, but there are a number of differences between these fish. You’ll want to learn as much as you can about each of them so that you can decide which one to buy for your fish tank.

In this article, you’ll learn various facts about cory catfish and otocinclus catfish. This will help you to have a good understanding of what each fish will bring to the table.

Learning about how big each of these fish will get will be an important factor. You’ll also discover whether cory cats and otos are considered to be good fish for beginners.

Otocinclus Fish Are Algae Eaters

Otocinclus Eating Algae Wafer

One thing to keep in mind is that otocinclus fish are algae eaters. You might be looking for a good bottom-dwelling fish that will help to keep your tank clean from algae.

Otos will absolutely help with this because they love to eat algae. They will eat algae off of the sides of the tank, and they’ll also eat algae that is near the substrate.

Cory catfish definitely don’t do this at all. You should know that cory cats don’t really like to eat algae.

You can feed cory catfish algae wafers and they will snack on them. However, they don’t really seek out algae because they aren’t considered to be algae eaters.

Otos are true algae eaters that will make sense in certain fish tank settings. If you’re looking specifically for an algae eater, then you should go with otos over cory catfish.

Don’t Buy Otos Unless You Have Lots of Algae

Do you have a lot of algae in your fish tank? Then it makes sense to buy several otos.

If you don’t have a lot of algae in the tank, then it might not be sensible to buy otos. These fish are going to need to have algae to eat in order to thrive in your aquarium.

Since cory catfish don’t eat algae, that’s not going to be a concern. You’ll just feed cory cats fish food and they will do well in the fish tank.

For beginners, it’s likely easier to just buy cory catfish. Otos serve a particular purpose, but that doesn’t mean that they won’t be useful fish to have in the tank for many enthusiasts.

Otos Aren’t As Easy to Care For

Another thing to know about otos is that they can be tricky to care for at first. They have particular dietary needs that must be met for them to acclimate to the tank.

Often, people buy otos and they wind up starving in the tank. This might also have to do with them being captured in the wild and not fed properly while being transported to pet stores.

Cory catfish are a lot easier to care for overall. They’re hardy fish that are easy to keep alive so long as you monitor the water parameters.

Otos will be hardier fish once they have acclimated to the tank. The first month or so of caring for otos will be the toughest period of time.

Cory Catfish Are Much More Laid Back

Group of Cory Catfish

Cory catfish have a reputation for being very laid-back fish that will not bother other fish in the tank. They just hang out at the bottom of the tank and sift through the substrate.

Otos aren’t nearly as relaxed as the cory catfish are. They’re more hyper and active fish by comparison.

For some, this might be a good thing since the otos can be fun to observe. However, the cory catfish are likely the better choice when you’re looking for peaceful fish that will mind their own business in the tank.

Which you will prefer will come down to what you’re looking for. These two types of fish truly are quite different personality-wise.

Both Types of Fish Are Schooling Fish

Both cory catfish and otocinclus catfish are schooling fish. That means that they do best when kept in a group.

You’re going to want to keep at least six of either fish in the aquarium. Cory catfish especially need to be kept in groups because they have been known to die when they get too lonely.

Otos do better in groups of six or more as well. However, some have noted that they have had success when keeping otos alone.

It’s just not the preferred way to keep these fish. They have an easier time surviving alone than cory cats do, but they’re still better off when put in a group of their own kind.

Otos Are a Bit Smaller on Average

Small Otocinclus on Glass

Otos are a bit smaller than cory catfish on average. Most cory catfish will be two and a half inches long at maturity, but some are a bit smaller.

An average oto catfish will grow to be between one and one and a half inches in length. Both catfish types are not that big overall, but there is still a size difference to note.

You can keep these fish in somewhat small fish tanks, but you don’t want to go too small. Since these fish are meant to be kept in groups, you want to ensure that all of the fish in the tank have enough room.

Can Cory Catfish and Otocinclus Catfish Live Together?

Yes, it is possible for cory catfish and otocinclus catfish to live together. Both are considered to be peaceful fish, and they will get along just fine.

You should remember to keep each of these types of fish in a school. That means at least six of each type of fish.

As long as they are able to school with others of their kind, it should be a good experience to keep them in the same tank. It’s actually pretty common for people to keep these two types of fish together.

Final Thoughts

Which fish you will like better will come down to your personal preference. Otos and cory cats do have some similarities, but they’re actually a lot different.

Otos are algae eaters that can be a bit finicky at times. Getting them to survive in the tank will require you to meet their dietary needs.

Cory catfish are easier to take care of overall. They’re hardy fish that are really good for beginners.

You can keep both types of fish together if you would like to. This can give you the best of both worlds.

Anyone who has a lot of algae in their fish tanks will benefit from having otos around. Enjoy your fish and take care of them well no matter what decision you make.