Mid-Stripe Otocinclus (Otocinclus affinis) Care Guide
Otocinclus affinis is a small dwarf suckermouth catfish from the Rio de Janeiro region of Brazil, a peaceful shoaling algae grazer for mature, planted tanks.
Overview
Otocinclus affinis (also placed in the genus Macrotocinclus) is a dwarf suckermouth catfish of the family Loricariidae (subfamily Hypoptopomatinae). It is a long-established aquarium "oto" and is often confused with similar Otocinclus species. FishBase gives a maximum standard length of about 5 cm.
Taxonomy
- Family: Loricariidae
- Scientific name: Otocinclus affinis
- Subfamily: Hypoptopomatinae
- Common synonyms: Golden Oto
Habitat
FishBase records the species from the vicinity of Rio de Janeiro, Brazil. Otos inhabit well-oxygenated streams and river margins, living in shoals and clinging to wood, stones and broad-leaved plants where they feed on the surface film. The genus has an air-breathing adaptation for low-oxygen periods.
Tank requirements
- Minimum tank volume: 60 L (16 gal)
- Adult size: 3-4 cm (1.2-1.6 in)
- Temperature: 24-28 °C (75-82 °F)
- pH: 6-7.5
- GH: 2-12 °dGH
- Group size: ≥6 individuals
- Lifespan: 8-12 years
Diet
The diet is algae-based, centred on diatoms and aufwuchs. It thrives in a mature, planted tank offering a continuous supply of soft green algae and biofilm, supplemented by blanched vegetables and algae wafers. Animal foods play only a minor role.
Compatibility
A peaceful, retiring fish, it is easily outcompeted by boisterous tankmates and should be housed with calm species. It is a social shoaler best kept in groups of at least six and is fully plant-safe, suiting communities of small tetras and Corydoras.
Breeding
As with other otos, the genus lays adhesive eggs that are not guarded, scattering them on plants and glass. Cooler, generous water changes are reported to encourage spawning.
Conservation status
The IUCN Red List assessed the species as Least Concern (2018).