Best for
Aquariums where its role fits: algae grazer.
O
Fish · Freshwater
Otocinclus
Otocinclus affinis
Otocinclus is a popular community aquarium fish.
Difficulty
Beginner
Aggression
0/10
Schooling
Yes
Size
5.00 cm
Minimum volume
40 L
Temperature
22.0-28.0 ºC
Zone
Bottom
Lifespan
5 years
Quick profile scan
fish
Territoriality
Low
Aggression
0/10
Activity
Slow
Thermal sensitivity
High
Bioload
Low
Speed
Slow
Predation risk
None
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Analyze volume, parameters, behavior and relationships with other species.
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Quick verdict
A practical summary to quickly decide whether it fits your aquarium.
Compatible with
Has positive or conditional references with species such as Cherry shrimp.
Typical risk
Stability depends on temperature, group size, and real compatibility.
Aquarium zone
Where it lives best
Surface
Midwater
Bottom
primary
Quick compatibility
Community signals
Shrimp
Compatible
Snails
Compatible
Slow fish
Compatible
Aggressive fish
Conditional
Small fish
Compatible
Large fish
Compatible
Delicate plants
Conditional
Buying decision
Before buying Otocinclus
Review these points before adding it to your aquarium. They are practical notes based on its profile, ecological data, and known relationships.
L
Adult volume
Make sure your aquarium is above 40 L before buying it.
G
Minimum group
Do not keep it alone if it needs a group; plan space for the right number of individuals.
C
Stable temperature
Avoid keeping it at the edges of its temperature range for long periods.
Parameters
Water conditions
pH
6.5 - 7.5
GH
5 - 15
KH
3 - 10
Temperature
22.0 - 28.0 ºC
Growth and behavior
Juvenile to adult
Juvenile
As a juvenile it feels safer in a group and usually uses the bottom with coordinated movement. An insufficient group can increase stress and erratic behavior.
Shift
The transition to adulthood usually brings more stable behavior when group size, space and parameters are suitable.
Adult
As an adult it keeps a strong social pattern and is more stable in adequate groups. In balanced communities it usually occupies the bottom without causing major conflict.
Ecological profile
Role and biological pressure
Algae Grazer
Bottom Cleaner
Small
Low
Moderate
None
Profile: algae-grazing species, with low bioload and primary use of the bottom. It should be kept in a group to show stable behavior and reduce stress. Temperature stability matters; avoid long-term maintenance at the edges of its range.
Ecological radar
profile
Territoriality
24%
Aggression
0%
Activity
24%
Thermal sensitivity
78%
Bioload
24%
Common mistakes
What to avoid
Keeping it in tanks below the recommended adult volume.
Keeping too few individuals for a social species.
Keeping temperature at the edges of the range for long periods.
Relations
Compatible with
✓
C
Cherry shrimp
Compatible
Main risk: Fin nipping
Low risk
Otocinclus affinis + Neocaridina davidi: cohabitation is usually viable if volume, parameters, groups and adult behavior are respected.
Essential care
Keep in groups of at least 6 specimens. It prefers tanks with open swimming space, some current and weekly water changes.
Daily time
10 min
Related biomes
Breeding
It is an egg-laying fish and relatively easy to breed. It scatters eggs among plants or over the substrate and provides no parental care.
Oviparous
Easy
Hembras más redondeadas y robustas. Machos más esbeltos y algo más amarillentos.
Alerts and health
- Mantener en grupo
- Espacio para nadar
- Acuario tapado
- Corriente suave a moderada
Common issues
Ich
Podredumbre de aletas
Parásitos externos
Expert notes
Interesting details
01
Es una de las especies más usadas en investigación biomédica
02
Sus rayas permanecen visibles durante toda la vida
03
Es un pez muy activo y gregario
Editorial confidence
Last review: June 2026
Content based on parameters, ecological profiles and manual relationships.
Profile data
Ecological profile
Manual relationships
General aquarium observation
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