Ruby Tetra

About

The Ruby Tetra (Axelrodi riesei) is a very small characid from the upper Río Meta basin in Colombia, a tributary of the broader Orinoco system. Its range appears to be genuinely limited, which probably explains why it turns up far less often in the hobby than its close relative Axelrodia stigmatias. The body color is a diffuse red that can vary considerably in intensity from fish to fish, and it does have a tendency to fade over time in aquarium conditions. Something worth keeping in mind when buying. Despite the peaceful temperament, this isn't really a fish to drop into a general community setup. Its small size makes it vulnerable around larger tankmates, and it does best either on its own or alongside equally small, non-aggressive characids and appropriately sized catfish. It's a shoaling species rather than a tight schooler, and males will carve out small territories and spar with each other regularly. Behavior that only becomes visible when you keep a group of at least eight to ten individuals. Soft, acidic water is genuinely important here rather than just ideal, given its blackwater origins. Breeding is achievable in a well-established aquarium with fine-leaved plants and leaf litter, and conditioned adults can spawn daily. Fry are tiny and benefit from the microorganisms that develop in decomposing leaf litter.