Max Size: 4cm

Common Otocinclus (Otocinclus vittatus)

The Common Otocinclus are an undemanding group that can tolerate a range of water conditions provided the water is kept clean and fresh. These Otos are a popular option for aquariums of all sizes due to their peaceful nature, interesting shoaling behaviours and algae-eating abilities, especially their ability to consume problematic diatomic brown algae. However, these fish can be somewhat skittish.

These Otos tend to stick together in groups, grazing on the same areas; therefore, it would be better to keep this species in groups of at least six. The bigger the group, the better; however, you must make sure the tank is large enough.

It would be beneficial if you densely plant the tank with large-leafed plants, smooth rocks and bogwood alongside a layer of rounded gravel as a substrate. This decor will provide hiding spots for your fish and offer surfaces on which algae can grow.

Unfortunately, this species's small size makes them an easy target; therefore, you should avoid larger or aggressive fish such as Cichlids and Oscars. Realistically you should keep these fish away from species with a fierce reputation or a mouth big enough to consume an Oto whole. Some popular choices of tankmates include medium-sized Barbs, Corydoras Catfish, Angelfish, Danios, Dwarf Gourami, Rasboras, Guppies, Tetras, Mollies and Zebra Loaches.

The Common Otocinclus has a simple cylindrical shape body that narrows towards the head and the caudal fin. These Otos have a firm mouth that they use to latch onto different surfaces. This fish displays a thick dark brownish-black horizontal line that runs down the lateral line from the nose to the caudal peduncle and a bold white line above that. Their fins are almost Transparent.


Common Otocinclus
Common Otocinclus
Common Otocinclus
Common Otocinclus
Common Otocinclus
Common Otocinclus
Quick Facts
Scientific NameOtocinclus vittatus
Other NamesLDA023, Dwarf Sucker, Otocinclus Catfish
OriginsArgentina, Brazil, Colombia, Peru, Venezuela
Aquarium LevelBottom
DifficultyBeginner - Intermediate
Best kept asGroups 6+
Lifespan3 - 5 years
Water Parameters
Water TypeFreshwater
PH5.5 - 7.5
GH8 - 10
70 - 79℉
21.1 - 26.1℃

Natural Habitat

Paraguay River
Xingu River
Tocantins River


The Common Otocinclus is primarily a herbivore which means they mainly live off algae. However, you still need to supplement this with other food. Dried food such as algae wafers or sinking pellets are ideal as they will not eat from the surface, and you should provide this every couple of days.

You can also feed your Otos on green vegetables such as spinach, lettuce and zucchini. Occasionally they may eat meaty foods such as carnivore pellets, tubifex, brine shrimp and mosquito larvae; however, make sure you remove any uneaten pieces from the aquarium after 24 hours.

It's essential that you observe algae levels in the tank and use this to decide how much supplementary food you need to supply. Finally, please make sure that you do not overfeed your Otocinclus.

Sexual Dimorphism

It is somewhat straightforward to differentiate between a male and female Common Oto. Females are typically larger and broader than the males, especially when viewed from above.

Other Catfish of interest

African Glass Catfish(Pareutropius debauwi)
Cuckoo Catfish(Synodontis multipunctatus)
Flagtail Catfish(Dianema urostriatum)
Glass Catfish(Kryptopterus vitreolus)
Marble Sturisoma Whiptail Catfish(Sturisoma aureum)
Royal Whiptail Catfish(Sturisoma panamense)
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Date Added: 30/06/2021 15:26:57 - Updated: 08/08/2022 15:18:46