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Maximum size : 2.5 cm

Ruby Tetra - Axelrodia riesei : Complete Fish Profile & Care Guide

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The charming Ruby Tetra (Axelrodia riesei) is a striking and peaceful species suitable for both nano and planted aquariums. These active little fish are a joy to watch, but their small size means that they are not suitable for community aquariums as they may feel overwhelmed and outcompeted. However, with proper care and specific conditions, Ruby Tetras can thrive and live a happy and healthy life in a well-maintained aquarium. These Tetras are gregarious and thrive best when kept in groups of at least 10 or more, where they can swim freely in their aquarium. Although not tightly schooling, they are social and will interact with each other, creating a lively and engaging display. Ruby Tetras are also territorial, and males may occasionally squabble. Therefore, ensure to provide hiding places and visual barriers to help keep the peace. When it comes to tankmates, choose small, peaceful species that won't cause any trouble for the Ruby Tetras. Some suitable companions include smaller species of Corydoras Catfish, Otocinclus Catfish, Pencilfish, Dwarf Cichlids, and other small blackwater Tetras. To provide the best home for your Ruby Tetras, make sure to set up a mature aquarium with a dark substrate and background, driftwood, and plenty of plant cover - both rooted and floating. These peaceful fish require a secure environment to thrive, and a well-planted tank with a network of hiding places and visual barriers will help them feel more at ease. Filtration should be efficient, and water movement should be gentle to prevent them from becoming stressed. Also, acclimate them carefully to avoid any shock or stress. Ruby Tetras are known for their striking red coloration on the top half of their body, which contrasts beautifully with their translucent fins and the transparent bottom half. They also have a black splotch at the end of their tail, making them an attractive and unique addition to any aquarium.\r\n

Ruby Tetra Photos

Sexual Dimorphism

Distinguishing between the male and female Ruby Tetras is a relatively simple task. Typically, the males are slightly smaller in size than the females, but have more intense and vibrant colors. As is the case with many Tetra species, the sexually mature female Ruby Tetras have a rounder body shape in comparison to their male counterparts.

Quick Facts

Scientific NameAxelrodia riesei
Year Described1966
Other NamesNone
Max Size2.5 cm
Aquarium LevelMiddle - Top
Best kept asGroups 8+
Lifespan5 - 10 years

Water Parameters

Water TypeFreshwater
PH4.5 - 6.5
GH3 - 12
TDS18 - 90
68 - 82
20 - 27.8

Natural Habitat

The Ruby Tetra can only be found in the Upper Rio Meta Basin, located east of Villavicencio, a significant tributary of the Rio Orinoco in Colombia, South America. While there are few details about their natural habitat, it is believed that the Ruby Tetra inhabits small forested tributaries rather than larger river channels, making them a truly unique and elusive species. These vibrant fish thrive in sluggish or almost still water filled with dense vegetation and an abundance of leaf litter. One of the most remarkable features of the Ruby Tetra's habitat is the soft, acidic water that is stained a rich tea colour from the tannins in the decaying leaves and wood. It's truly a mesmerizing sight and a testament to the adaptability and resilience of these remarkable creatures. Join us as we delve deeper into the world of the Ruby Tetra, and discover the incredible beauty and diversity of this rare and elusive species. From the pristine waters of the Upper Rio Meta basin to the unique characteristics of their natural habitat, the Ruby Tetra is a true wonder of the natural world.
 Orinoco - Venezuela
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In home aquariums, Ruby Tetras have been successfully bred, and although small numbers of fry may appear in heavily planted tanks, raising larger numbers requires a separate spawning aquarium. Setting up a spawning aquarium with matching water parameters and fine-leaved plants like Java Moss, on which the fish can scatter their eggs, is recommended. These fish are conditioned to spawn daily, so leaving the adults in the spawning aquarium for a few days before reintroducing them to the main aquarium will limit the chances of eggs and young being consumed. After hatching, the fry will become free-swimming in 24-48 hours and will require miniature food like infusoria to thrive.

Diet & feeding

In the home aquarium, Ruby Tetras are considered relatively undemanding and adaptable when it comes to their diet. They can generally consume various kinds of food, including high-quality flake, granules, and pellets, as long as the food is of a suitable size for their small mouths. Additionally, incorporating occasional treats of live, freeze-dried, and frozen foods can help provide a varied and balanced diet for optimal health and vibrant colouration.\r\n

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