Otocinclus Care 101: Complete Guide For Aquarium Hobbyists

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Besides being aesthetically-pleasing, the Otocinclus is also celebrated for its ability to eat algae. In fact, these delightful fish, also known as otto catfish, are considered to be some of the best around for eating algae in your aquarium. Combine this with their friendliness, and it becomes easy to understand why so many consider these fish to be an essential part of any thriving tank.

Why Do People Love Otocinclus?

The fact that Otocinclus are so easy to care for is another reason why people are so fond of them. They are an exceptional choice for those who are just beginning to build their very first fish tank.

At the same time, it is also easy to neglect them. Many lose their Otocinclus in the first month, and there is certainly no reason for this. Caring for them is extremely simple, but there are still a number of things you are going to want to keep in mind. This includes getting the best tank, ideal aquarium roommates, the best plant life for otto catfish, and much more.

If you are new to the world of Otocinclus care, not to worry! We’re going to tell you everything you need to know about these freshwater beauties. From there, we can also discuss the basics of bringing them home for the first time.

What Exactly Are The Otocinclus?

First, let’s start with an overview of exactly what we’re talking about, when we talk about the otto catfish.

Belonging to the Loricariidae fish family, the Otocinclus represents a genus of catfish with a freshwater background. It is estimated that there are nineteen different species of the otto catfish. They are noted for their easygoing demeanor, relative hardiness, and for coming in a wide variety of styles and colors. For these reasons, as well as many others, they are widely considered to be one of the top fish choices for a beginner aquarium.

They have a lifespan of roughly three to five years, rarely measure more than one to two inches, and can often be identified by the presence of a brown stripe. Most otto catfishes are going to have that stripe somewhere along the body.

Suitable for a peaceful family aquarium situation, these fish are herbivores. This means you’re going to have a lot of different options for feeding them. That is yet another feature to the Otocinclus that people seem to appreciate.

Some also like to call them dwarf suckers. They can be found throughout freshwater sources in South America. This extends to Venezuela and North Argentina.

Everything Else You Need To Know About Otocinclus Appearance

We’ve mentioned the brown stripe that can be found along many examples of the otto catfish. However, there are a few more pieces of information on their appearance that is worth covering in greater detail.

While you want a tank large enough to keep them comfortable and happy, one of the main things to remember with these fish is that they are very small. They rarely grow to exceed three inches in size. You might be interested in learning that they have distinctly strong mouths. This makes latching on to things a good deal easier for them. It also partially explains why otto catfish are so good at eating algae. Their bodies are generally cylindrical in shape, and you can also always spot this catfish example by the presence of armor plating all over their bodies.

With a limited ability towards breathing air, telling the difference between males and females can be a little tricky. As a general rule, females are usually broader in their sizing.

What About The Different Types Of Otocinclus?

Another nice thing about this type of fish would be the fact that there are so many different colors and types to choose from. In terms of things like size and behavior, you’re not going to see too many differences from one type to the next. One example of an exception to this would be the Otocinclus flexilis. This particular offering is on average the largest of the different types, with an average of roughly 2.2 inches.

Here are a few examples of different types of otto catfish:

  • Common: Noted for being a prominent member of the Amazon River, the Common Otocinclus, as the name implies, is the most common of all the different types. Speckled brown in appearance along the top, and then white along the bottom, you will also want to keep in mind that their fins are almost completely transparent.
  • Golden: If the brown looks more like a golden color, you probably have a Golden Otocinclus.
  • Zebra: You can probably picture exactly what the Zebra Otocinclus looks like, just from the name alone!
  • Silver: The brown stripe here is very interesting, as it tends to be silverer in appearance.
  • Dwarf: The best way to distinguish these from Common Otocinclus comes down to the caudal fins. The design will be very different on the Dwarf Otocinclus.

A Few More Notes On Important Examples Of Otocinclus Behavior

In terms of Otocinclus behavior traits, the key phrase to remember is the following: Lowkey.

By their nature, Otocinclus prefer to avoid trouble. They are not aggressive in any form or fashion. Their preference will always be to stay out of the way of anything else you may keep in your tank. This is another reason why people like them for aquariums of all experience levels.

At the same time, their avoidance behavior can create its own potential problems. This is really only the case if your tank is too small. Chances are, you are going to have more than just a single otto catfish in your tank. The recommended size for any aquarium that is going to include these fish is at least ten gallons.

For a variety of reasons, particularly in terms of comfort, as well as room to grow your tank, many experts suggest instead opting for something in the 20-gallon range. The choice is ultimately yours to make, but stay away from anything smaller than ten.

Otocinclus tend to be very skittish around larger fish. There is a reason for this, owing to the fact that many other fish see them as a potential snack. While this is something to keep in mind with regards to otto catfish tankmates, it also goes a long way towards explaining their behavior. If something scares them, they will almost certainly swim away very, very quickly. This is good for avoiding predators, but it can make catching them a pain!

They tend to hang out along the bottom of your tank. You can also find them along the surface of any plants or decorative items you may have in the tank. Remember that above all else, their favorite thing to do in the whole world is eat algae. They prefer to do this in groups, grazing casually throughout the day. If there is no algae to be found, they will simply move on to seek out another surface. Take note that groups of Otocinclus get along just fine with one another.

At this point, we can really start to dig into everything you need to remember, if you are planning to buy Otocinclus for the first time.

Otocinclus Affinis

How To Build The Perfect Aquarium For Otocinclus

Because of their hardiness to tank conditions, as well as their fairly simple needs, shopping for a suitable tank for Otocinclus is fairly straightforward. Because they come from South American, their needs are going to be mostly the same as what you’d suspect from freshwater fish. They need something for the bottom of the tank, appropriate roommates, access to light, some plant life and other decorative accessories, and lots of room.

We’ve already covered the importance, but let’s keep a few more things in mind.

For instance, the finer the grain, the better, when it comes to what to put on the bottom of the tank. A coarse grain may cause harm to their bodies, remembering how much time they tend to spend along the bottom of the tank. You’re also going to want to be sure they have things like rocks, bits of wood, and other plants that offer hiding spots and lots of yummy algae. You’re going to want a temperature somewhere in the range of seventy-two to seventy-nine degrees Fahrenheit. The most comfortable pH level for the Otocinclus is going to be somewhere between 6.8 and 7.5. You’re going to want to keep soft water in your tank, with the levels never getting any higher than 15dH.

Also, in case you were wondering, a 10-gallon tank can comfortably hold anywhere between four and six of these fish. Again, if you’re planning to add some other fish to the aquarium, you’re going to want to go bigger than ten gallons. Twenty gallons will give you room to grow, while also letting you get a nice collection of fish right from the start.

Which Fish make The Best Tankmates For Otocinclus?

Now, at this point, you’re probably wondering if it’s a good idea to shop for other fish to keep your Otocinclus company. While the otto catfish doesn’t really care one way or the other, there are in fact several different fish that can work well in the tank with them.

As a good general rule, we would suggest avoiding large fish, or any fish with a notable trait of being aggressive. So, for example, betta fish are probably not going to be good tankmates for your Otocinclus. Many examples of cichlids are not going to be appropriate for sharing quarters with your Otocinclus either.

So, which ones are going to be okay? Beyond invertebrates like snails and shrimp, guppies, mollies, tetras, cherry barbs, and Corydoras catfish are all great options that are worth exploring in greater detail.

Also, remember that otto catfish do very well indeed together. If you’re planning to have more than one, and you really should, the accepted minimum is considered to be four.

Resting on Java

What Are The Best Things To Feed My Otocinclus?

Thanks to the fact that they are herbivores, you’re going to find yourself with a variety of appealing options for what you can feed them.

As we’ve touched on a few times, Otocinclus love to eat algae. This makes them ideal for keeping the stuff out of your tank, but it also means you’re giving them a ready-made food source. However, while they do love to eat algae, something they do in the wild, you do not want to only feed them this. They are going to need a rounded diet, and you need to make sure that diet will meet all of their herbivore nutritional needs. No live animals, or indeed anything that comes from something that was once living.

In terms of things you can feed them besides algae, you might be surprised by just how many options are really out there. Click here to check out a complete guide to feeding your Otocinclus. A varied diet will keep them healthy and happy for the entirety of their average lifespans.

A Few Final Otocinclus Care Tips

Before we wrap things up, we wanted to leave you with a few more tips and suggestions for ensuring your otto catfish are receiving the very best of care:

  • You don’t want to just leave the algae in your tank unchecked either. You will need to make sure it isn’t overwhelming the tank. This is particularly important with regards to other fish in the aquarium.
  • Disease is not a significantly big deal with this type of fish. Ich is one possible disease they can get, if the tank is not properly maintained at all times. If you notice sluggishness, combined with a decrease in their overall appetite, then there is a good chance that they need to be treated. Quarantine and keep a close eye.
  • Breeding. If the conditions are ideal, males will begin the process by chasing the female around. If they are successful, you should have fry in a couple of days.
  • Make sure to keep their diet nice and varied. This will ensure the best possible health.
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Jeff Colt

Jeff Colt

Hello, I'm Jeff- an aquarium enthusiast with over 25 years of experience caring for a wide array of tropical fish, including koi, goldfish bettas, cichlids and more! For me: Aquariums are like jello - there's always room for more!

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