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Maximum size : 3.5 cm

Cenepa Red Pencilfish - Nannstomus sp : Complete Fish Profile & Care Guide

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The stunning Cenepa Red Pencilfish are a relatively new addition to the fishkeeping hobby. This pretty little fish was first considered a sub-species of the Dwarf Pencilfish but was later recognised as its own distinct species. The Cenepa Red Pencil fish is a beautiful, petite, active and personable fish that makes a great addition to a nano or well-planted aquarium. However, these fish do not make an ideal member of a typical community aquarium due to their small size and somewhat timid nature. If you wish to keep Cenepa Red Pencilfish with other species, they should ideally be small, non-aggressive species such as smaller Tetras, Micro Rasboras and Dwarf Barbs. You can also house these fish with Corydoras Catfish and amicable Plecos. These Pencilfish also make an ideal dither fish for Apistogrammas and other Dwarf Cichlids as they typically inhabit the middle to upper areas of the aquarium and do not actively predate fry. Though naturally sociable, Cenepa Red Pencilfish is a shoaling rather than schooling species with rival territorial males sparring regularly during the day. For this reason, you should use a spacious aquarium and arrange the d├ęcor so plenty of broken lines of sight are provided. In addition, it would be best to keep these fish in a group of at least 10, preferably more. Keeping these fish in larger groups will not only prevent aggression on single individuals but will make the fish feel safer, leading to more natural behaviour and a better display. The ideal aquarium setup for Cenepa Red Pecilfish would be a heavily planted aquarium with a dark substrate and sheltered areas to help reduce skittishness and offer refuge for sub-dominant individuals. Floating plants, driftwood branches and dried leaf litter are all useful, and you will need gentle filtration. An air-powered sponge filter is more than adequate. These fish require stable water conditions; therefore, you should never add them to a biologically immature aquarium. A Cenepa Red Pencilfish is a small, slender fish. Male Cenepa Red Pencilfish display vibrant scarlet colouration that extends into their dorsal fin and borders their caudal and anal fins in black and white. The Female's only visible colour is a splash of red on the dorsal fin and operculum, similar to the well-known Dwarf Pencilfish.

Cenepa Red Pencilfish Photos

Sexual Dimorphism

It is simple to differentiate between the male and female Cenepa Red Pencilfish. Adult males are slimmer and far more vibrantly coloured than females. Another way to determine the sex of this species is to watch their behaviour; males will frequently present and nip at each other, while females are very docile.

Quick Facts

Scientific NameNannstomus sp
Other NamesSuper Red Coral Pencilfish, Albertini Super Red Pencilfish
Max Size3.5 cm
Aquarium LevelMiddle - Top
DifficultyBeginner - Intermediate
Best kept asGroups 5+
Lifespan3 - 5 years

Water Parameters

Water TypeFreshwater
PH4.0 - 7.0
GH1 - 12
TDS18 - 90
75 - 82
23.9 - 27.8

Natural habitat

The Cenepa Red Pencilfish is endemic to the Rio Amaya, a tributary of the Rio Morona, one of the Amazon's headwaters in Peru in South America. The fish live in tannin-stained, clear blackwaters with virtually no mineral content.

How to breed the Cenepa Red Pencilfish

It is possible to breed Cenepa Red Pencilfish, but it can be quite challenging for the lesser experienced hobbyist. First, you will need to set up a separate breeding tank with mature water with a low PH level, plenty of fine-leaved plants or java moss, and marbles, pebbles or small rocks on the bottom of the tank. The lights will need to be relatively dim, and you will also need gentle air-driven filtration. Once the Pencilfish are ready to spawn, they will swim next to each other, and the male will bump the female's abdomen; this is how the male will fertilise the eggs. The female will then drop a few eggs at a time, which will fall into the plants or the substrate until she has run out of eggs. After all the eggs have been laid, removing the parents is advisable as they are known to be voracious egg eaters if given the opportunity. The eggs will usually hatch around 36 to 72 hours later, depending on the temperature. The tiny fry will first consume their yolk sacs and then become free-swimming around 3 to 4 days later. Once their yolk sacs have disappeared, you can provide the fry with infusoria, rotifers, and powdered first foods, moving on to larger foods such as microworm and baby brine shrimp as they develop. If your fry is well fed, it will take approximately two months for them to reach 1 cm in length, after which they will start to take on the same colouration as the adults.

Diet & feeding

In the home aquarium, the Cenepa Red Pencilfish will readily accept most good quality dried foods such as granules, flakes and sinking pellets. These modern food products have been developed to provide all adequate nutrition to maintain your fish's health and dietary requirements. Providing additional foodstuffs such as live, frozen, and freeze-dried meals such as bloodworm, daphnia, and tubifex once or twice a week will provide other benefits to your fish's health and well-being but is not a must for this fish. It should be noted that bloodworms should only be given as an occasional treat and should not be used as the staple diet as they are difficult for fish to digest and can potentially cause blockages. This fish is an omnivore in the wild, meaning it will consume some vegetable matter. Although most modern fish foods take this into account and include them in their products, you can still supplement your fish's diet with blanched vegetables such as spinach, broccoli, and zucchini. Ensure you do not overfeed your fish and remove any leftovers the following day.

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