Coral Red Pencilfish (Nannostomus mortenthaleri) are small, colorful fish that make a great addition to any peaceful community tank. These fish are part of the Lebiasinidae family and are related to other pencilfish species.
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The name “Nannostomus” comes from the Greek words “nannos,” meaning dwarf, and “stoma,” meaning mouth. “Mortenthaleri” is named after the German aquarist, Hans-Georg Mortenthaler, who discovered the species.
Coral Red Pencilfish are mid-dwellers that prefer a well-planted aquarium with plenty of hiding spots. They are omnivores and will eat a variety of foods, including flakes, frozen, and live foods.
These fish are known for their peaceful temperament and can be kept with other small, non-aggressive fish. They are schooling fish and should be kept in groups of at least six.
Coral Red Pencilfish are native to the Rio Negro basin in Brazil and can be found in slow-moving streams and rivers with plenty of vegetation. They prefer water temperatures between 73-82°F (23-28°C) and a pH range of 4.0-7.0.
One interesting fact about Coral Red Pencilfish is that they are known to “play dead” when threatened. They will roll over on their side and remain motionless until the danger has passed.
In the aquarium trade, Coral Red Pencilfish may also be known as Mortenthaler’s Pencilfish or Red Pencilfish. They are a relatively new addition to the hobby, having only been discovered in the 1990s.
Overall, Coral Red Pencilfish are a beautiful and interesting addition to any peaceful community tank. With proper care and tank mates, they can thrive and bring a splash of color to your aquarium.
Coral Red Pencilfish Key Information
Coral Red Pencilfish (Nannostomus mortenthaleri) is a stunning freshwater fish that boasts a vibrant red coloration with a striking iridescent gold lateral stripe running along its slender body. The fins are translucent with a hint of red, adding to the fish’s overall elegance. The intensity of the red hue may vary depending on the individual fish, its age, and its environment.
| Family | Lebiasinidae |
| Origin | Rio Negro basin, Brazil |
| Price | Moderate |
| Common Names | Coral Red Pencilfish, Mortenthaler’s Pencilfish, Red Pencilfish |
| Variants | None |
| Ideal Tank Size | 20 gallons or larger |
| Water Parameters | Temperature: 73-82°F (23-28°C), pH: 4.0-7.0, Hardness: 1-10 dGH |
| Lifespan | 3-5 years |
| Full Size | 1.2-1.6 inches (3-4 cm) |
| Natural Environment | Slow-moving streams and rivers with abundant vegetation |
| Behavior | Peaceful, schooling fish |
| Habitat Preference | Mid-level dweller, prefers well-planted aquariums with hiding spots |
| Aquarium Decoration | Densely planted with plenty of hiding spaces, dark substrate, driftwood |
| Ideal Tank Mates | Other peaceful, small fish (e.g., tetras, rasboras, small catfish) |
| Fish to Avoid | Large, aggressive fish that may bully or eat them |
| Best Foods/Diet | Omnivorous; accepts flakes, frozen, and live foods |
| Disease | Susceptible to common freshwater diseases if water conditions are poor |
| Sex-Switch | No |
| Gender Differences | Males are typically more slender and colorful than females |
| Care Level | Easy to moderate |
| Breeding Level | Moderate; egg-scatterers that require specific conditions for successful breeding |
Ideal Tank Mates for Coral Red Pencilfish
In order to create a peaceful and enjoyable environment for everyone, it is essential to thoughtfully choose tank mates for the Coral Red Pencilfish. It is important to consider their peaceful behavior, size, and water parameter needs. The ideal companions should have similar temperaments, sizes, and habitat preferences. Here, we present 10 perfect tank mates for the Coral Red Pencilfish, along with detailed explanations of their compatibility.
1. Neon Tetras (Paracheirodon innesi)
Neon Tetras are a classic choice for a peaceful community tank. Their small size, vibrant colors, and gentle disposition make them an excellent match for Coral Red Pencilfish. Both species thrive in similar water conditions and enjoy the company of their own kind, creating a visually stunning display as they school together in the aquarium.
| Common/Market Names | Neon Tetra |
| Price Range | Low |
| Care Level | Easy |
| Behavior | Peaceful, schooling |
| Life Span | 5-8 years |
| Max Size | 1.5 inches (3.8 cm) |
2. Ember Tetras (Hyphessobrycon amandae)
Ember Tetras are another small, peaceful species that complement Coral Red Pencilfish beautifully. Their warm, reddish-orange coloration adds a delightful contrast to the Pencilfish’s vibrant red hues. Both species appreciate a well-planted aquarium with plenty of hiding spots and enjoy the safety of schooling with their own kind.
| Common/Market Names | Ember Tetra |
| Price Range | Low to Moderate |
| Care Level | Easy |
| Behavior | Peaceful, schooling |
| Life Span | 2-4 years |
| Max Size | 0.8 inches (2 cm) |
3. Pygmy Corydoras (Corydoras pygmaeus)
Pygmy Corydoras are a delightful addition to a Coral Red Pencilfish tank. These tiny, peaceful catfish occupy the bottom level of the aquarium, scavenging for leftover food and helping to maintain a clean substrate. Their unique appearance and entertaining behavior make them a joy to observe, while their small size ensures they won’t outcompete or disturb the Pencilfish.
| Common/Market Names | Pygmy Cory, Dwarf Corydoras |
| Price Range | Low to Moderate |
| Care Level | Easy |
| Behavior | Peaceful, social |
| Life Span | 3-5 years |
| Max Size | 1 inch (2.5 cm) |
4. Cherry Shrimp (Neocaridina davidi)
Cherry Shrimp are a fantastic invertebrate companion for Coral Red Pencilfish. These colorful, algae-eating shrimp help maintain a clean and healthy aquarium while adding visual interest. Their small size and peaceful nature ensure they won’t pose a threat to the Pencilfish, and in turn, the Pencilfish are unlikely to bother the shrimp.
| Common/Market Names | Cherry Shrimp, Red Cherry Shrimp |
| Price Range | Low to Moderate |
| Care Level | Easy |
| Behavior | Peaceful, active |
| Life Span | 1-2 years |
| Max Size | 1.5 inches (3.8 cm) |
5. Harlequin Rasboras (Trigonostigma heteromorpha)
Harlequin Rasboras are a striking and compatible tank mate for Coral Red Pencilfish. Their unique triangular shape and vibrant red and black coloration create a stunning display when schooling alongside the Pencilfish. Both species share a preference for well-planted aquariums and thrive in similar water conditions.
| Common/Market Names | Harlequin Rasbora |
| Price Range | Low |
| Care Level | Easy |
| Behavior | Peaceful, schooling |
| Life Span | 5-8 years |
| Max Size | 1.8 inches (4.5 cm) |
6. Celestial Pearl Danios (Danio margaritatus)
Celestial Pearl Danios, also known as Galaxy Rasboras, are a stunning and peaceful species that make excellent tank mates for Coral Red Pencilfish. Their small size, iridescent spots, and subtle red hues complement the Pencilfish’s vibrant coloration. Both species enjoy a well-planted aquarium and thrive in similar water conditions.
| Common/Market Names | Celestial Pearl Danio, Galaxy Rasbora |
| Price Range | Moderate |
| Care Level | Easy to Moderate |
| Behavior | Peaceful, schooling |
| Life Span | 3-5 years |
| Max Size | 1 inch (2.5 cm) |
7. Endler’s Livebearers (Poecilia wingei)
Endler’s Livebearers are a colorful and lively addition to a Coral Red Pencilfish tank. These small, peaceful fish come in a variety of colors and patterns, adding visual interest to the aquarium. They occupy the upper levels of the tank, leaving plenty of space for the Pencilfish to swim and explore.
| Common/Market Names | Endler’s Livebearer, Endler’s Guppy |
| Price Range | Low to Moderate |
| Care Level | Easy |
| Behavior | Peaceful, active |
| Life Span | 2-3 years |
| Max Size | 1.8 inches (4.5 cm) |
8. Dwarf Gouramis (Trichogaster lalius)
Dwarf Gouramis are a peaceful and colorful species that can coexist harmoniously with Coral Red Pencilfish. Their unique shape, vibrant colors, and gentle demeanor make them an attractive addition to the community tank. While slightly larger than the Pencilfish, Dwarf Gouramis are not aggressive and will not outcompete or bully their smaller tank mates.
| Common/Market Names | Dwarf Gourami, Flame Dwarf Gourami, Powder Blue Dwarf Gourami |
| Price Range | Moderate |
| Care Level | Easy to Moderate |
| Behavior | Peaceful, can be territorial with their own species |
| Life Span | 3-5 years |
| Max Size | 3.5 inches (9 cm) |
9. Kuhli Loaches (Pangio kuhlii)
Kuhli Loaches are an entertaining and peaceful bottom-dwelling species that can safely share an aquarium with Coral Red Pencilfish. These eel-like fish have a unique appearance and fascinating behavior, often hiding during the day and becoming more active at night. Their presence helps keep the substrate clean and adds an element of surprise to the tank.
| Common/Market Names | Kuhli Loach, Coolie Loach |
| Price Range | Low to Moderate |
| Care Level | Easy to Moderate |
| Behavior | Peaceful, nocturnal |
| Life Span | 10+ years |
| Max Size | 4 inches (10 cm) |
10. Otocinclus Catfish (Otocinclus spp.)
Otocinclus Catfish, or “Otos,” are small, peaceful algae eaters that make excellent tank mates for Coral Red Pencilfish. These industrious little fish help maintain a clean aquarium by consuming algae and biofilm, while their small size ensures they won’t disturb the Pencilfish. Otos are social creatures and should be kept in groups, adding another layer of interest to the tank.
| Characteristic | Description |
|---|---|
| Common/Market Names | Otocinclus Catfish, Oto, Dwarf Suckermouth Catfish |
| Price Range | Low to Moderate |
| Care Level | Easy to Moderate |
| Behavior | Peaceful, social |
| Life Span | 3-5 years |
| Max Size | 2 inches (5 cm) |
By selecting tank mates from this list, you can create a diverse, colorful, and harmonious community aquarium that showcases the beauty of Coral Red Pencilfish while ensuring the well-being of all its inhabitants.
FAQs about Coral Red Pencilfish
What is the minimum tank size for Coral Red Pencilfish?
A 20-gallon tank or larger is recommended for a school of Coral Red Pencilfish, as they require ample swimming space and a well-established ecosystem.
How many Coral Red Pencilfish should be kept together?
Coral Red Pencilfish are schooling fish and should be kept in groups of at least 6 individuals to ensure their comfort and well-being.
Are Coral Red Pencilfish easy to breed?
Breeding Coral Red Pencilfish can be challenging, as they require specific water conditions and a dedicated breeding setup. However, with proper research and preparation, hobbyists can successfully breed these fish.
How often should I feed my Coral Red Pencilfish?
Feed your Coral Red Pencilfish small amounts of food 2-3 times daily, ensuring that they consume all the food within 2-3 minutes to prevent overfeeding and maintain good water quality.
Do Coral Red Pencilfish jump out of the tank?
While not known for being avid jumpers, Coral Red Pencilfish may jump out of the tank if startled or stressed. To prevent this, keep the tank covered and maintain a calm, stress-free environment.
Can Coral Red Pencilfish be kept with shrimp?
Yes, Coral Red Pencilfish can be kept with peaceful, similarly-sized shrimp species like Cherry Shrimp, as they are unlikely to harm or consume them.
Are Coral Red Pencilfish sensitive to water changes?
Like most fish, Coral Red Pencilfish can be sensitive to sudden changes in water parameters. Always perform gradual water changes (10-15% per week) to avoid stressing your fish.
How long do Coral Red Pencilfish live?
With proper care and maintenance, Coral Red Pencilfish can live for 3-5 years in captivity.
Do Coral Red Pencilfish have any special lighting requirements?
Coral Red Pencilfish do not have any specific lighting requirements, but they benefit from a well-planted aquarium with moderate lighting to promote plant growth and provide shelter.
Can Coral Red Pencilfish be kept with bettas?
It is not recommended to keep Coral Red Pencilfish with bettas, as bettas may become aggressive towards the smaller pencilfish, causing stress and potential injury.
