Otocinclus (Oto) care guide
Otocinclus macrospilus (as a representative; many otos are traded under this name) · Loricariidae
Otocinclus (Otocinclus macrospilus (as a representative; many otos are traded under this name)) is an aquarium animal. It belongs to the Loricariidae family. It is native to O. macrospilus is one of the commoner otos in the hobby, endemic to the Upper Amazon in Peru; it is frequently mislabelled as O. affinis or O. vittatus.. Water temperature: 21°C – 26°C. pH: 5.5 – 7.5. Care difficulty: Moderate.
How do you care for Otocinclus (Oto)?
| Temperature | 21°C – 26°C |
|---|---|
| pH | 5.5 – 7.5 |
| Placement | Bottom and leaf level; a tank of at least about 45 × 30 cm (~41 litres), soft water (1–12 dGH), a mature planted tank. |
| Growth | Very small: about 3.5 cm (1.4 in) standard length for O. macrospilus; FishBase lists O. affinis, the oto traded most, at up to about 5 cm, so size depends on which oto is sold. |
| Difficulty | Moderate (imported fish can be delicate, usually from starvation in transit) |
| Family | Loricariidae |
How do you trim and propagate Otocinclus (Oto)?
Feeds mainly on algae and micro-organisms. Offer fresh vegetables (courgette, cucumber, blanched spinach) and dried foods (algae wafers, spirulina); go easy on live or frozen food because it needs little protein.
What problems affect Otocinclus (Oto)?
So shy it is out-competed for food; newly imported fish are often thin and weak.
How do you fix Otocinclus (Oto) problems?
Add to a mature tank with some algae; keep a group of at least 6 with peaceful tankmates such as small characins, dwarf cichlids and small corydoras.
Where does Otocinclus (Oto) come from?
O. macrospilus is one of the commoner otos in the hobby, endemic to the Upper Amazon in Peru; it is frequently mislabelled as O. affinis or O. vittatus. · Biotope regions: South America.
What should you know before buying Otocinclus (Oto)?
Keep a group; it is not a replacement for feeding, whatever the algae-eater label says.
Sources
- Otocinclus macrospilus — Seriously Fish
- Otocinclus affinis — FishBase
Care details checked against these sources on 2026-10-29.
See Otocinclus (Oto) in a living world
- Iwagumi Triad — aquarium
- Dutch Street Aquascape — aquarium
Last updated · Open the interactive 3D guide · All species care guides