Otocinclus Catfish
Otocinclus are small, peaceful freshwater catfish that are highly regarded for their algae-grazing abilities. They have a slender body, sucker-shaped mouth and distinctive markings, making them an excellent addition to peaceful community aquariums.
 
Key Features
Common Name: Otocinclus Catfish, Dwarf Suckermouth Catfish
Scientific Name: Otocinclus spp.
Family: Loricariidae
Origin: South America
 
Care Requirements
Minimum Aquarium Size: 60 Litres
Water Level: Bottom / Lower Levels
Diet: Herbivore / Algae Grazer
Activity: Active throughout the day
Social Behaviour: Best kept in groups of 5 or more
Temperature: 22–28°C
pH: 6.0–7.5
Hardness: Soft to moderately hard
Stable water conditions are important for Otocinclus. Regular water changes and good filtration should be maintained while avoiding sudden changes in temperature or water chemistry.
A mature aquarium is strongly recommended, as established tanks provide the natural algae and biofilm these fish rely on.
Provide plenty of plants, driftwood and other surfaces for grazing. Live plants are particularly beneficial as they provide additional grazing areas and natural cover.
A fine or smooth substrate is recommended to prevent damage to their sensitive undersides and mouths.
Good filtration and oxygenation are important, but avoid excessively strong currents that prevent the fish from comfortably grazing.
DIET & FEEDING
Although Otocinclus are excellent algae grazers, they should not be expected to survive solely on aquarium algae.
Supplement their natural diet with:
Algae wafers
Spirulina-based foods
Sinking vegetable foods
Blanched zucchini
Blanched cucumber
Spinach
Other suitable vegetables
Fresh vegetables should be removed before they begin to deteriorate and affect water quality.
FEEDING NOTE
Newly introduced Otocinclus can sometimes struggle if placed into immature or very clean aquariums with little natural algae or biofilm available.
Ensuring there is an established food source and providing supplementary feeding is particularly important during the first few weeks after introduction.
 
Temperament
Temperament: Very Peaceful
Otocinclus are extremely peaceful and are well suited to community aquariums.
Suitable tankmates include:
Small tetras
Rasboras
Small peaceful gouramis
Small livebearers
Corydoras
Other peaceful community fish
Avoid aggressive, predatory or highly territorial species that may harass or prey upon them.
GROUP SIZE
Otocinclus are social fish and are best kept in groups of 5 or more. Larger groups generally provide greater confidence and encourage more natural behaviour.
 
Notes
OTOCINCLUS CATFISH (OTOCINCLUS SPP.)
These active little catfish spend much of their time grazing on algae and biofilm from aquarium glass, plants, driftwood and other surfaces. They are social fish and should ideally be kept in groups, where they will display more natural and confident behaviour.
Otocinclus are particularly sensitive to poor water quality and should only be introduced to mature, established aquariums with a good supply of natural biofilm and algae.
Otocinclus should be added to mature, stable aquariums rather than newly established tanks. Their small size and sensitivity to poor water quality make proper acclimation and stable aquarium conditions particularly important.
A well-established aquarium with live plants, natural biofilm and supplementary feeding will provide the best environment for these fascinating little algae grazers.