© CHUCAO / CC BY-SA 3.0Otocinclus
Otocinclus, often called "otos," are small South American catfish prized for grazing algae off aquarium glass and plant leaves, making them a favorite choice for planted tanks. Reaching just 3 to 5 cm, they have a calm, peaceful temperament that fits well alongside other community fish and delicate aquascapes. They feel most secure when kept in a small group rather than alone. With a typical lifespan of 3 to 5 years, otos do best when their algae diet is supplemented with tablet foods to keep their nutrition balanced. Considered suitable for beginners, they're a popular addition to any newly established planted aquarium.
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Apply as a breederAbout Otocinclus
Otocinclus are peaceful algae-eating catfish that grow to 3-5cm with a 3-5 year lifespan. Beginner-friendly, they're a popular cleanup crew for planted aquariums.
7 things to know before welcoming a Otocinclus
1Great Algae Eaters
Otocinclus naturally graze algae off glass and plant leaves. Since algae alone isn't always enough nutrition, supplementing with tablet food helps keep them healthy.
2Happier in Groups
They tend to feel calmer and less stressed when kept in a small group rather than alone. Consider bringing home several at once.
3Peaceful Temperament
Otos are gentle by nature and rarely bother other fish or nibble on live plants, making them easy to add to community or planted tanks.
4Compact Size
Adults typically reach only 3 to 5 cm, so they're a good fit even for smaller aquariums.
5Best for Established Tanks
They do best in tanks that have already matured enough to grow some algae, since that's their main food source. Consider the tank's condition before adding them.
6Provide Hiding Spots
They like to tuck themselves into hiding spots, so plants or driftwood give them places to settle in and feel secure.
7Lifespan of 3-5 Years
With good care, otos typically live 3 to 5 years. Consistent water quality and a balanced diet are key to a long life.
Frequently asked questions about Otocinclus
- Q.What should I feed Otocinclus?
- A.Their main food is the algae that grows naturally in the tank, but that alone often isn't enough, so it's best to supplement with algae tablet food. Pay extra attention to feeding when algae is scarce.
- Q.How many should I keep together?
- A.Otocinclus tend to settle in better when kept in a small group rather than alone. Consider bringing home a few at a time, sized to your tank.
- Q.Can they live with other fish?
- A.Yes, their peaceful temperament makes them easy to keep with many other community fish, and they rarely damage live plants, which suits planted tanks well.
- Q.Can I add them right after setting up a new tank?
- A.A newly set up tank usually doesn't have enough algae yet, so it's better to wait until the tank has matured and algae has started to grow before adding them.
- Q.Are Otocinclus subject to CITES?
- A.No, Otocinclus are not subject to CITES.
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Learn more about Otocinclus in the encyclopedia
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Care difficulty, lifespan, size and diet — all basics covered.
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