Twig Catfish Quick Stats
Minimum Tank Size: 20 Gallons (80 Litres)
Care Level: Difficult
Water Conditions: PH 6.0-7.0 Soft to Moderately Hard
Temperature: 75-79°F (24-26°C)
Maximum Size: 6 inches (15 cm)
The name twig catfish (Farlowella) is an umbrella term used for at least 37 species of catfish, but usually only two of these species are found in the aquarium trade: F. Acus and F. vittata. However, F. Acus is endangered, and it is believed few are imported these days. F. vittata make up the bulk of twig catfish found in aquariums.
These fish are native to Venezuela and Colombia, and are found in heavily vegetated and flooded areas with submerged roots and branches. The name twig catfish comes from their impressive camouflage abilities, and due to their elongated body and brownish color, they can easily be mistaken for a twig. Even in the home aquarium, they often stay motionless in an attempt to blend in with their surroundings.
In fact, these fish rarely swim, and their movements can be more accurately described as hopping from spot to spot in the aquarium. Once in position, they will attach their suckermouth to an object, and stay there virtually motionless. Even when being captured, they often won’t react in the hopes of being mistaken for a twig.
In the home aquarium, they can grow to a maximum length of 6 inches (15 centimeters), though they often remain smaller. When it comes to lifespan, there are numerous conflicting reports (and publications) stating they can live anywhere from five to fifteen years in captivity. It’s reasonable to assume a well-cared for twig catfish can live between five and ten years – though they rarely reach this age due to their sensitivity to poor water conditions.
These fish can be housed in a 20-gallon aquarium, but it can be difficult for all but the most experienced aquarists to maintain perfect water conditions in a tank this small. And it can’t be stressed enough that these fish need absolutely pristine water conditions to survive. A much better aquarium choice for these fish would be any tank larger than 40 gallons, as it provides more stable water conditions.
Adding to the difficulty in keeping these fish, is the fact they only tend to thrive in species only tanks. Their peaceful and shy nature makes them poor candidates for most community tanks. Even when kept with smaller fish, they are unable to compete for food, and often become the victim of aggression.
When setting up a tank for twig catfish, plenty of driftwood or bogwood should be provided to create perches and hiding places for these fish. A dark substrate is preferred, though a sand substrate closely mimics their natural habitat. While not entirely necessary, the addition of live plants is appreciated and can help maintain the tank’s water quality.
Any aquarium containing twig catfish must be properly filtered. There are few other commonly available fish who are as sensitive to poor water conditions as twig catfish, and it’s highly recommended to over-filter their tank. A hang-on-back filter is a good choice for a twig catfish tank and I personally recommend the Aquaclear Power Filter. Not only is it rugged and durable, but with proper maintenance it should give you years of trouble free operation. It’s also a good idea to include a sponge filter to increase the biological filtration and aeration of the tank (though an air stone will work in its place).
Twig catfish primarily eat a vegetarian diet, and they should be fed a combination of sinking herbivore pellets and lightly blanched vegetables. For their prepared food, I strongly recommend Hikari Algae Wafers. As for vegetables, they greedily accept cucumber and zucchini medallions, lettuce, spinach, and broccoli.
While they will continuously graze on algae, algae alone will not sustain them and they should be fed prepared foods and vegetables. I can’t tell you the number of times I’ve heard fish store employees telling people they don’t need to feed a pleco or a twig catfish, because ‘they live on algae’. The truth is they need a varied diet, and without feeding them, twig catfish will waste away and die.
They can also occasionally be offered live or frozen foods, such as blood worms, daphnia, gut-loaded brine shrimp, and black worms (or tubifex in Europe). But these should only be an occasional treat.
Twig catfish are generally easy to sex, and the males have a broader snout than the females. Also, the males are larger than the females and will develop odontotes as they age, which helps them to be easily identified.
If enough males and females are kept together, and are well fed, they will usually breed on their own in an aquarium. Since these fish do not automatically pair off, it’s usually best to start off with a fair number of juveniles, and wait for a male and a female to form a bond.
To trigger breeding, it’s imperative to keep the water quality as pristine as humanly possible. They should also be fed high quality foods, and it’s important to get a true herbivore fish food to offer to them.
Once the proper conditions are provided, twig catfish will normally spawn after the lights have been shut off at night. They spawn on flat surfaces, and usually the eggs are deposited on the aquarium glass, though you may also find them on rocks or driftwood.
The males show parental care, and will stay near the eggs, guarding them, and gently fanning them with their fins. The eggs will usually hatch in about a week, and will become free swimming after five days.
Twig catfish fry are very difficult to raise, and even experienced breeders often experience high losses. While the parents are sensitive to water conditions, the fry are even more sensitive. And they are difficult to feed on top of that.
The fry should be fed blanched lettuce and spinach, and it should be very soft before it is offered to them. Also, to ensure there is enough algae for them to graze on, a system for providing algae covered rocks should be setup prior to breeding.
To do this, a half dozen rocks should be kept in water near a window, where algae can grow on their surface. Once they are completely covered in algae, one rock can be added to the aquarium. After most of the algae has been eaten by the fry, the rock should be removed and placed back by the window. A new algae covered rock should then be added to the aquarium. By using this method, there will always be at least one algae covered rock to feed the fry in the aquarium.
But even with these methods, many of the fry will normally die, so don’t be disheartened if you end up with significant early losses.