Twig Catfish (Farlowella)

Farlowella acus

Catfish

The Twig Catfish is an extremely elongated, master-of-camouflage suckermouth catfish from South America. True to its name, it mimics a dead twig perfectly, spending most of its time motionless on branches or plant leaves. It is a specialized aufwuchs and algae grazer that requires a mature tank, high oxygenation, and plenty of driftwood. They are completely peaceful but highly sensitive to fluctuating water parameters.

At a Glance

Adult Size16 cm
Body ShapeEel
Growth RateSlow
TemperamentPeaceful
Water TypeFreshwater Only
Flow PreferenceModerate
Waste OutputMedium
StockingSolo or group

Tank Requirements

Minimum Volume110 L
Minimum Length80 cm
FlowModerate
Water TypeFreshwater Only
Must-Haves in the Tank
Driftwood (Digestion/Hiding)Established Algae (Otocinclus)

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Water Parameters

Temperature2326°C
pH67.2
Hardness310 dGH

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Temperament & Compatibility

Aggression LevelPeaceful
1/10
Where They Swim
Surface
Mid-level
Bottom
Stocking Guidelines
Keep at Least1 (solo is fine)
Max per TankNo limit
Can Live Alone?Yes
Behavior Traits
Shy / Slow Moving (Easily Stressed)

Available Varieties

Each variety inherits the species defaults above. Only differences are highlighted.

Standard / Unsexed

The standard representation of the species, often sold as juveniles before sexual dimorphism is apparent.

Same care requirements as the base species

Also known as: Juvenile

Male

Mature males develop rows of short bristles (odontodes) along the sides of their broad snout, used during breeding and territorial displays.

Same care requirements as the base species

Also known as: Bristle Snout

Female

Mature females possess a slightly narrower and completely smooth snout, lacking the odontodes seen in males.

Same care requirements as the base species

Also known as: Smooth Snout

Twig Catfish (Farlowella) Care Guide Summary

The Twig Catfish (Farlowella), scientifically known as Farlowella acus, belongs to the Catfish family group. Adults reach a maximum size of approximately 16 cm and have a eel body shape with a slow growth rate. Classified as peaceful, this species primarily occupies the mid-level and bottom zones of the aquarium and produces a medium level of biological waste.

To thrive, the Twig Catfish (Farlowella) requires a freshwater only aquarium with a minimum volume of 110 litres and a tank length of at least 80 cm. Water temperature should be maintained between 23°C and 26°C, with a pH range of 67.2 and a general hardness of 310 dGH. A moderate water flow is preferred. An aquarium test kit can help you monitor these values.

The Twig Catfish (Farlowella) is a rewarding species to keep, provided its core environmental needs are met. This species is available in 3 varieties: Standard / Unsexed, Male, and Female. Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.

Twig Catfish (Farlowella) Habitat Setup

When setting up an aquarium for the Twig Catfish (Farlowella), a moderate water flow best suits their natural preferences. Because this species occupies the mid-level and bottom zones, the aquarium layout should prioritise open swimming space in the centre of the tank for free movement and sufficient floor space with hiding spots among rocks, wood, or dense planting. Useful additions include driftwood, which can serve as both a hiding place and a dietary supplement and an established tank with natural algae growth, as they depend on it as a primary food source.

Twig Catfish (Farlowella) Compatibility Notes

Classified as peaceful, the Twig Catfish (Farlowella) is adaptable and can be kept singly or in a small group, offering flexibility when planning a community tank. When choosing tankmates, boisterous or fast-moving tankmates may cause this species undue stress. Selecting tankmates that favour different water layers from the mid-level and bottom zones can help reduce competition and territorial overlap.

Frequently Asked Questions About Twig Catfish (Farlowella)

How big does Twig Catfish (Farlowella) get?+
Twig Catfish (Farlowella) (Farlowella acus) typically reaches a maximum adult size of approximately 16 cm. They have a eel body shape and a slow growth rate.
What tank size does Twig Catfish (Farlowella) need?+
A minimum aquarium volume of 110 litres and a tank length of at least 80 cm are recommended for Twig Catfish (Farlowella). This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Twig Catfish (Farlowella) need?+
Twig Catfish (Farlowella) thrives in freshwater only conditions with a temperature range of 23–26°C, a pH between 6 and 7.2, and a general hardness of 3–10 dGH. A moderate water flow is preferred.
Is Twig Catfish (Farlowella) peaceful or aggressive?+
Twig Catfish (Farlowella) is classified as peaceful with an aggression score of 1 out of 10. They are generally well-suited to peaceful community tanks.
Can Twig Catfish (Farlowella) live alone?+
Yes, Twig Catfish (Farlowella) can be kept singly or in a group. They are flexible and adapt well to both setups.
Does Twig Catfish (Farlowella) have any special tank requirements?+
Yes. Twig Catfish (Farlowella) benefits from driftwood (digestion/hiding) and established algae (otocinclus) in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.

Similar Species

Whiptail Catfish

Rineloricaria sp.

Catfish
12 cm Peaceful

A highly cryptic, peaceful, and extremely slender catfish that mimics a twig or dead leaf. They are excellent scavengers and biofilm grazers that require smooth sand and driftwood to thrive. They are completely non-aggressive, lack the heavy armor of larger plecos, and do well in peaceful community setups.

Striped Raphael Catfish

Platydoras armatulus

Catfish
22 cm Peaceful

A highly robust, armored catfish native to the Amazon and Orinoco basins. Famous for their ability to produce audible squeaking or grunting sounds when distressed or defending territory. They are nocturnal scavengers that spend most of the day hiding in driftwood or caves. Note: Their rigid pectoral spines can easily become tangled in standard aquarium nets.

Pictus Catfish

Pimelodus pictus

Catfish
12 cm Mostly Peaceful

An extremely active, striking silver catfish with black spots and incredibly long barbels, native to South America. While peaceful toward similarly sized tank mates, they are highly effective nocturnal predators that will easily swallow small fish (like Neon Tetras) whole. They are scaleless and possess sharp pectoral spines that can easily become entangled in aquarium nets.

Otocinclus

Otocinclus vittatus

Catfish
4 cm Peaceful

A small, peaceful, and highly popular algae-eating catfish native to South America. They are obligate shoaling fish that thrive in mature, heavily planted aquariums with steady water parameters and a constant supply of soft green algae and biofilm. They are extremely sensitive to uncycled or pristine/new tanks without natural food sources.

Bristlenose Pleco

Ancistrus cirrhosus

Catfish
13 cm Peaceful

A highly popular, hardy, and relatively small suckermouth catfish. Excellent algae eaters that stay much smaller than Common Plecos, making them suitable for standard aquariums. They require dietary wood (driftwood) to aid in digestion and plenty of hiding caves.

Common Pleco

Hypostomus plecostomus

Catfish
45 cm Mostly Peaceful

A heavily armored, nocturnal catfish famous for eating algae. However, they grow incredibly large, produce massive amounts of waste, and frequently outgrow standard aquariums. They require driftwood in their diet for digestion. As they age, they may become territorial or develop a taste for the slime coat of slow-moving, flat-bodied tank mates.