Coral Red Pencilfish - Nannostomus mortenthaleri : Complete Fish Profile & Care Guide
Table of contents
Introduction
The captivating Coral Red Pencilfish (Nannostomus mortenthaleri), a relatively recent addition to the fishkeeping hobby, was accurately described only in 2001. Initially considered a subspecies of the Dwarf Pencilfish, it was later acknowledged as a unique species in its own right. Coral Red Pencilfish are petite, active, and charming, making them an excellent choice for nano or well-planted aquariums. However, their small size and somewhat timid nature render them less suitable for typical community aquariums.
For successful cohabitation with other species, opt for smaller, non-aggressive species like smaller Tetras, Micro Rasboras, and Dwarf Barbs. Coral Red Pencilfish can also coexist with peaceful Corydoras Catfish and Plecos. As ideal dither fish for Apistogrammas and other Dwarf Cichlids, they generally inhabit the middle to upper areas of the aquarium and do not prey on fry.
Though inherently social, Coral Red Pencilfish is shoaling rather than schooling fish, with rival territorial males engaging in frequent sparring. A spacious aquarium with décor arranged to create numerous broken lines of sight is essential. Ideally, these fish should be kept in groups of at least 10, with larger groups promoting natural behaviour and improved displays while mitigating aggression.
An optimal habitat for Coral Red Pencilfish includes a setup with a dark substrate, abundant vegetation, areas for shelter, floating plants, driftwood branches, and dried leaf litter to mimic their natural environment. Gentle filtration, preferably through an air-powered sponge filter, is advisable to maintain water quality without creating excessive turbulence. To ensure their health and well-being, these fish should be introduced into a well-established aquarium that has achieved biological maturity, thereby ensuring stable water parameters.
Coral Red Pencilfish is small and slender, with males displaying red colouration on their entire body and fins, while females exhibit a pinkish hue. Both sexes feature two prominent, thick, lateral black stripes and a white base at the anterior portion of the dorsal fin in males. Recently, a Super Red Coral Pencilfish variant has emerged in the hobby. Yet to be formally described, it is currently designated as Nannostomus sp. Albertini Super Red, as this stunning fish, may eventually be classified as a completely new species of pencilfish.
Coral Red Pencilfish Photos
Sexual Dimorphism
Distinguishing between male and female Coral Red Pencilfish is straightforward. Adult males are more slender and exhibit more vibrant colours than females. Additionally, males display a white marking at the base of their dorsal fin from a young age. Observing their behaviour can also help determine their sex; males often engage in displays and nipping at each other, while females remain docile and more passive.
Quick Facts
| Scientific Name | Nannostomus mortenthaleri |
|---|---|
| Year Described | 2001 |
| Other Names | Peruvian Red Pencilfish, Ruby Red Pencilfish, Red Arc Pencilfish, |
| Kingdom | Animalia |
| Classification | Actinopterygii |
| Order | Characiformes |
| Family | Lebiasinidae |
| Genus | Nannostomus |
| Origins | Peru |
| Max Size | 3.5 cm |
| Temperament | Peaceful |
| Aquarium Level | Middle - Top |
| Difficulty | Beginner - Intermediate |
| Shoaling | Yes |
| Best kept as | Groups 5+ |
| Diet & Feeding | Omnivore |
| Reproduction | Egg Depositor |
| Average Lifespan | Up to 5 Years |
Water Parameters
| Water Type | Freshwater |
|---|---|
| pH | 4.0 - 7.0 |
| GH | 1 - 12 |
| TDS | 18 - 90 |
| ℉ | 75 - 82 |
|---|---|
| ℃ | 24 - 28 |
Natural Habitat
The Coral Red Pencilfish, an exceptional species, originates from the Nanay River Basin in the Loreto Department of Peru, with additional sightings reported in the neighbouring Rio Tigre River system. These distinguished fish flourish in the tannin-rich, tranquil, and soft acidic waters found in small rivers, swamps, and floodplain lakes of their native region. Their natural environment is marked by lush aquatic vegetation, intricate submerged woody structures, and a significant presence of leaf litter. The Coral Red Pencilfish's vivid appearance, coupled with its specific habitat preferences, underscores its intriguing nature.
Breeding
Breeding Coral Red Pencilfish is achievable but can be challenging for less experienced hobbyists. To begin, set up a separate breeding tank with mature water, a low pH level, plenty of fine-leaved plants or java moss, and marbles, pebbles, or small rocks at the bottom. Ensure the lighting is dim, and utilize gentle air-driven filtration. When the Pencilfish are ready to spawn, they will swim beside each other, with the male bumping the female's abdomen to fertilize the eggs.
The female will then release a few eggs at a time, which will fall into the plants or substrate. Once all the eggs are laid, remove the parents to prevent them from eating the eggs. Depending on the temperature, the eggs will hatch within 36 to 72 hours.
The tiny fry will first consume their yolk sacs and become free-swimming in approximately 3 to 4 days. After their yolk sacs are gone, feed the fry infusoria, rotifers, and powdered first foods, transitioning to larger foods like microworms and baby brine shrimp as they grow. With proper feeding, the fry should reach 1 cm in length in about two months and begin to exhibit adult colouration.
Diet & Feeding
In the confines of an aquarium, Coral Red Pencilfish demonstrates a low level of dietary pickiness, willingly consuming a variety of prepared foods, including micro pellets, freeze-dried options, and a broad spectrum of flake foods. However, for the promotion of their optimal health and to enhance the vibrancy of their colouration, it is recommended to enrich their diet with live or frozen offerings such as bloodworms, mosquito larvae, and brine shrimp.
Frequently asked questions
Videos
9 tank mate ideas for the Coral Red Pencilfish
Looking for some awesome tank mate ideas for your Coral Red Pencilfish? Look no further! Here are 9 of the most captivating & fascinating options that will liven up your aquarium!
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