Otocinclus Catfish — Fish Profile
Otocinclus vittatus
Quick Specs
| Adult Size: | 2.0" |
| Temperament: | peaceful |
| Care Level: | intermediate |
| Min Tank Size: | 20 gallons |
| Temperature: | 72-79°F |
| pH Range: | 6.5-7.5 |
| Diet: | herbivore |
| Origin: | South America (Amazon Basin) |
| Lifespan: | 3-5 years |
Overview
Otocinclus, affectionately called 'ottos', are small, dedicated algae-eating catfish that stay much smaller than plecos. They are peaceful, schooling fish that cling to glass, plants, and rocks while constantly grazing on soft algae and biofilm. They should always be kept in groups of 3+ and introduced only to mature, cycled tanks with a steady natural algae supply.
Care Guide for Otocinclus Catfish
Tank Setup
Otocinclus Catfish requires a minimum tank size of 20 gallons. Maintain water temperature between 72°F and 79°F, with a pH range of 6.5 to 7.5. A properly sized tank with adequate filtration and regular water changes is essential for long-term health. When housing Otocinclus Catfish with other species, always choose a tank size that accommodates the most demanding fish in the community.
Feeding
Otocinclus Catfish is a herbivore feeder. Provide a varied diet appropriate for herbivore species to ensure optimal health and coloration. Feed small portions 2–3 times daily, and remove uneaten food after a few minutes to maintain water quality.
Temperament & Compatibility
This species is classified as peaceful. Otocinclus Catfish reaches an adult size of 2.0 inches and has a care level of intermediate. Always research compatibility before adding new fish to an established aquarium. Individual temperament can vary, so monitor new introductions closely for the first 48 hours.
Origin & Lifespan
Otocinclus Catfish originates from South America (Amazon Basin) and has an expected lifespan of 3-5 years when kept in proper water conditions with appropriate tank mates and diet.
Compatible Tank Mates
🟢 Good Tank Mates
🟡 Caution Tank Mates
🔴 Risky Tank Mates
Recommended for Otocinclus Catfish
Omega One Veggie Rounds — $9.49Sinking algae rounds for herbivorous catfish
Expert Care Tips for Otocinclus Catfish
- Mid-size tank: Otocinclus Catfish needs 20+ gallons. Choose a tank at least 2× as long as the fish's adult size (2.0") for adequate swimming room.
- Tropical range: Keep Otocinclus Catfish at 72–79°F. A 50W heater per 10 gallons is a safe rule of thumb for stable temperature.
- Narrow pH tolerance: Otocinclus Catfish only tolerates pH 6.5–7.5. Test your tap water before buying — adjusting pH is harder than choosing the right fish for your water.
- Peaceful community fish: Otocinclus Catfish works well in community tanks. Still, avoid housing with fish large enough to eat them — a 2.0" fish is vulnerable to anything with a mouth bigger than 2×.
- Acclimation: Always drip-acclimate Otocinclus Catfish over 30–45 minutes. Match temperature and pH gradually to prevent osmotic shock.