Ruby Tetra Care Guide
Axelrodia riesei · Freshwater Fish
What Ruby Tetra look like
The Ruby Tetra (Axelrodia riesei) is a diminutive, laterally compressed fish, reaching a maximum adult size of approximately 0.6 to 0.8 inches (1.5 to 2.0 cm). Its body exhibits a slender, fusiform shape, characterized by a translucent integument that is suffused with a striking ruby red hue, particularly concentrated around the caudal peduncle where a vivid red spot is prominently displayed. This unique coloration gives the impression of an internal luminescence, enhancing its visual appeal. The species possesses a small, terminal mouth with fine dentition adapted for grazing on small food particles. Notably, the Ruby Tetra lacks significant sexual dimorphism; however, males may exhibit slightly more intense coloration. Its defensive adaptations include a schooling behavior that provides safety in numbers, and its small size allows it to evade larger predators effectively. The species is also equipped with a well-defined lateral line system, aiding in the detection of water movements in its environment.
Behavior & temperament
Ruby Tetras are inherently social and thrive in groups, exhibiting a strong tendency to form schools in the mid to upper water column. They are typically found in slow-moving or still waters, often dwelling among submerged vegetation and leaf litter. Their breeding behavior is characterized by egg scattering, where females release eggs into the water column, allowing for external fertilization by males. Ruby Tetras are generally peaceful and exhibit a calm temperament, although they can display slight territoriality during breeding periods. Their social hierarchy is relatively egalitarian, as they do not establish a strict dominance hierarchy within their schools.
Diet & feeding
In the wild, Ruby Tetras are omnivorous, feeding primarily on small invertebrates, algae, and detritus. In captivity, they require a varied diet that includes high-quality flake food, micro-pellets, and live or frozen foods such as brine shrimp and daphnia to ensure optimal health and coloration.
Behind the name
Axelrodia (named in honor of Herbert R. Axelrod, a prominent aquarist); riesei (named after the collector, Dr. Hans Riese).
Plan your tank
Check the numbers before you buy: tank volume, a stocking plan, cycle progress, water changes, and your ongoing care routine.
Keeping Ruby Tetra?
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