Betta rubra Care Guide - Setup, Diet & Breeding

Betta rubra is a small wild betta with a striking red-and-black appearance. Mature males commonly show a rich reddish body, dark transverse markings and flashes of blue or green iridescence in the fins and scales. Females are generally subtler in colour, but still display attractive patterning when settled and mature.

Unlike the familiar Siamese fighting fish, Betta rubra is a mouthbrooding species rather than a bubble-nest builder. Its reproductive behaviour and more natural body shape make it especially appealing to aquarists interested in wild bettas and observing less-commercialised fish behaviour.

In the aquarium, these bettas are alert, intelligent and inquisitive. They frequently investigate their surroundings and may spend time hovering among plants, roots and leaf litter. Males can be territorial, although the species is often less relentlessly aggressive than selectively bred splendens-type bettas.

Wild Betta rubra live in dim, tannin-stained habitats beneath the forest canopy. Their natural surroundings are typically rich in submerged roots, fallen leaves and aquatic cover, with subdued light and relatively little open swimming space. This environment also helps explain their preference for calm, sheltered aquariums.

Betta rubra comes from northern Sumatra in Indonesia, particularly the Aceh region. It inhabits shaded, slow-moving forest streams, peat-influenced waters and small pools associated with dense tropical vegetation.

A single Betta rubra or a compatible pair should have at least 40 litres, with a footprint of roughly 60 by 30 cm; a larger aquarium is preferable for a group or community. Use a secure lid because wild bettas can jump, and provide gentle filtration with minimal current. A dark sand or fine-gravel substrate, subdued lighting, dense plants, floating cover, wood, caves and a layer of dried leaves create the sheltered, blackwater-style setting they favour. Soft, mildly acidic to neutral water and stable conditions are important.

Males reach about 5 cm (2 inches) in total length, while females are usually slightly smaller at around 4.5 cm (1.8 inches).

Betta rubra are primarily small predators and should receive a varied, protein-rich diet. Suitable foods include live or frozen daphnia, mosquito larvae, brine shrimp, blackworms and other appropriately sized aquatic invertebrates. High-quality betta pellets can supplement the diet, but live and frozen foods are particularly useful for conditioning adults and encouraging natural feeding behaviour.

Betta rubra can be kept in a peaceful community aquarium with similarly calm, small fish such as tiny rasboras, peaceful tetras and small kuhli loaches, provided the aquarium offers ample cover. A species aquarium or carefully selected pair setup is often the safest option. Avoid fin-nipping fish, boisterous species and other territorial bettas. Small shrimp and juvenile fish may be eaten, while multiple males require generous space and visual barriers to limit conflict.

Betta rubra are paternal mouthbrooders. Condition a compatible pair with plenty of live or frozen foods, then provide quiet surroundings and visual cover. After spawning, the male gathers the eggs and incubates them in his mouth for around 10 to 14 days, depending on temperature. The female may help retrieve stray eggs, although the male usually performs most of the incubation. Newly free-swimming fry can be offered tiny live foods such as microworms and baby brine shrimp.

Males are typically larger and more vividly coloured, with stronger red tones, darker markings and more noticeable blue or green iridescence in the fins. Females are usually shorter-bodied, rounder through the abdomen and less intensely coloured, often showing a visible ovipositor when mature.