Purple Pencilfish

The Purple Pencilfish originally comes from South America, where it is mainly native to Peru. It belongs to the family of slender tetras and is mostly a calm fish. With a final size of about 3.5cm, it is one of the smallest representatives of Nannostomus. It is a beautiful, reddish-violet shimmering freshwater fish with black vertical stripes, which attracts everyone’s attention in the aquarium.

Care in the aquarium

Due to its higher maintenance requirements, the Purple Pencilfish is classified as moderately difficult and rather not suitable for beginners. Nannostomus rubrocaudatus should be kept in an aquarium with a length of least 60cm and should be kept in a group of at least 10 animals (ideally with more females than males) for him to feel comfortable. In groups that are too small, it can be much more fearful and shy. Socializing with very lively or larger fish should be avoided, but Corydoras and other peaceful bottom dwellers are very well suited for this. The tank should not only have enough space, but also be well planted and structured to offer the animals a place to retreat if necessary. Care should also be taken to ensure that the water is nitrate-free, clean and soft. Keeping the Purple Pencilfish in a blackwater tank is ideal and you should not go without regular water changes, as this fish is quite sensitive to pollution and suboptimal water parameters. These fish feel particularly comfortable in a tank with dense vegetation, which offers enough hiding places, but also enough swimming space. Floating plants are also welcome in the aquarium, since the Purple Pencilfish is mainly found near the water surface and likes to hide between the roots of the floating plants.

Feeding

In its natural habitat, the Purple Pencilfish feeds on small worms and crustaceans, insect larvae and approach food. In the aquarium, it is optimally fed with small amounts of live and frozen food, but will also accept fine dry food.

Sexual characteristics and breeding

The sexes are differentiated primarily based on the physique and the shape of the fins. While the somewhat fuller females have pointed anal fins, the males have these rounded and lined with black. For breeding, fine-leaved plants should be present in the tank, between which the females spawn. In order to increase the fish’s willingness to spawn, more live food is fed and the tank is darkened. The water should also be very soft, rather acidic and, above all, clean. After spawning, the eggs should be transferred to a separate breeding tank or the adults should be removed from the tank, since dwarf ornamental tetras are spawn predators and do not stop at their own offspring. After about 1-2 days, the dwarfs hatch and, after the yolk sac has been consumed, can be fed with infusoria, copepods and newly hatched Artemia nauplii. For healthy growth of the young fish, the water should be cooler.