Aqua Fauna Research Logo


Author : Efrain Silva


The fish you know as Otocinclus, others may know as Dwarf Sucker – cool names, aren’t they? This fish has a notable black stripe seen all the way across its mid - section, front to back, and bright black as well to match it. It’s got very thin, flaky (if it were a human being, we might call it ‘pasty’) fins. Some also call it the Oto.

This type of Catfish, in its other forms, instead has a white underbelly area and is black - striped on top, with black & grey markings all over. Its color complexion is pretty unique to behold. Check it out when you can.


A strict diet regimen is always a good idea but not always a must, and with a fish like this, think about feeding some soft algae — you may find that this is more than enough, in the case of the Oto (I like that nickname already, you can tell….). A little algae will go a long way.

And if you are someone who forgets to feed your pets regularly, let me offer a tip — try leaving plenty of raw, live algae in the walls of the fish tank ; over time, as the fish gets hungry, it will eat on its own (and plenty), and you won’t have to constantly remind yourself to drop in new fish pellets every day or two.


The “origin place” for this fish would be that of South America, especially Venezuela and Argentina alike. In Venezuela, which so happens to house “Angel Falls”, the largest waterfall in the world, this fish can be seen swimming at the very bottom depths of the falls (how brave of it to venture to do so).

In Argentina, you may find it around a number of riverbeds and oceans alike as well. This fish seems not to mind where it wanders as it is truly free - spirited and passively wild in nature. You can’t compare it to any other.

Roommate Situation

Finding this special guy a life partner (or partners) can be a challenge worth every second as every creature deserves a chance to share life with someone. If you’ve got your little Oto in a 10 - gallon aquarium tank, then here’s a good tip to get you started : Consider a Marimo Moss Ball as a roommate. It was, for my best friend, the best choice he ever made in regards to his own fish tank. His fish likely thanked him for it.

Why not some Vampire Shrimp or Red Cherry Shrimp to invite to the tank? These are also peaceful, solid roommates. You might try Ivory Snails as well — much good has been said about these as roommates to the Otocinclus.

Other Facts to Note

The biggest one spotted has been 5.5 cm! It can adapt itself uniquely to breathe air above water. All in all, it makes a splendid pet — so why haven’t you gotten one already? The pet stores are waiting for you to take them home!