Zebra oto

Zebra oto or tiger oto (Latin – Otocinclus cocama) is one of the smallest catfishes from Loricariidae family. It will tirelessly help you fight with algae in a tank. However, it is more seldom encountered in aquariums than Otocinclus affinis.

Habitat in the wild

Zebra oto was first described in 2004. Currently tributaries of the Ucayali and Maranon River in Pery are considered to be the fish habitat.

Otocinclus cocama is encountered in large numbers in thickly planted areas where there is a lot of grass growing under water.


Body shape is the same as that of other Otocinclus species. This is a small fish with a suckermouth and an armored body.

The fish body length is about 4.5 cm, but the males are smaller. Lifespan is up to 5 years.

The fish coloring makes it different from other species of its kind. Head and back have bluish white or a bit yellowish coloring. The top of the head and the area between the fish nostrils is black, bottom side of the fish head is light yellow; sides of the fish head and areas behind its eyes are black with V-shaped white stripe on the fish face.

On the fish back and sides there are 4 black or dark gray elongated spots: the 1st one is located at the beginning of the dorsal fin, the 2nd one is behind the dorsal, the 3rd one is between the dorsal and fluke fins, the 4th is at the beginning of the fluke.

The fish has a black spot on its tail stalk and W-shaped vertical stripe on its fluke fin, which makes is differ from other Otocinclus species.

Difficulties in keeping

The fish is rather demanding and troublesome to keep. Some of species sold in pet shops are still delivered from their habitats, which leads to high mortality rates of the fish during the adaptation period. When keeping the fish in a home tank, it requires perfectly clean water and nutritious diet.

Scientific nameOtocinclus cocama
Common NameZebra oto, tiger oto
Tank size13 gallons and more
DietOmnivorous bottom feeder
Temperature22 – 26 °C (71,6-78,8°F )
pH 6.0 – 7.5
Size 4.5 cm (1.8 inches)
Lifespanup to 5 years

Keeping in a tank

Zebra oto requires thickly planted tank with a stable biological balance in it. It is desirable to add some fluctuants and snags into the tank as well as to put some fallen leaves on its bottom.

The fish requires crystal clean water with low level of nitrates and ammonia content. Ideally you should use external filter, but taking into account the fact that usually the fish is kept in small sized tanks, internal water filter will do as well.

Weekly water renew and using special tests to define tank water parameters is a must in this case.

The most suitable tank water parameters are the following: temperature 22 – 26°C, pH: 6.0 – 7.5, hardness 36 – 179 ppm.


Zebra oto has a vegetarian diet. In the wild it feeds with algae/biological fouling. During the adaptation period the fish should have enough of green and brown soft algae in a tank. The algae should form a biofilm on the tank plants and decorations. Zebra oto will scrape and eat this biofilm. Without it the fish will starve.

With time the fish will get used to eat some other food. This can be spirulina or pellets for phytovorous catfish species. Except artificial food you can feed with natural food – vegetables, for example. Cucumbers, marrow squash and parboiled spinach is the best option in this case.

Otocinclus cocama can eat other kind of food as well, but its diet must contain large amount of various vegetable food.


Zebra oto is a rather peaceful fish and it can be kept in a community tank, but its small size and timid temper make it rather vulnerable. Therefore, it is better to keep the fish separately in a species tank or together with other small peaceful fishes such as guppy or neon tetra. Small sized shrimps will also do as a oto tank mates, red cherry, for example.

Zebra oto is a schooling fish, which should be kept in a tank in a school of at least 6 species. The tank should be thickly planted, since the fish is active during the day and it eats algae fouling from tank plant leaves. Besides, tank plants are also a shelter for the fish.

Without tank plants and shelters oto won’t feel safe in a tank and this stress can easily lead to various health issues and early death of the fish.

There are some comments saying that oto nips other fishes bodies from sides, but I’d say that it must have happened due to stress or lack of vegetable components in the fish diet.

Sexual dimorphism

Reproductive male is 5-10 mm smaller than the female; it has a cone shaped urogenital papilla behind its anus and the female fish doesn’t have it.


Though there are some reports about successful zebra fish breeding, they yield little information. Apparently, juveniles are very small and require large amount of algae to feed.