Species description

Care, breeding and tankmates

Fish profile

Temperament

Semi-aggressive

The Blue-bellied Night Wanderer is extremely peaceful and quite shy. They are schooling fish that rely on the presence of conspecifics to feel secure and display their best natural behaviors. Without a suitable group size or hiding places, they will remain highly stressed and largely invisible.

Diet

Carnivore

In the wild, they likely feed on minute aquatic invertebrates and zooplankton. In the aquarium, they require tiny, appropriately sized foods such as microworms, newly hatched brine shrimp, and fine powdered dry foods. They may struggle to accept larger standard flakes or pellets, making live or frozen micro-foods essential.

Sex ratio

Group

Sexual dimorphism is subtle, but mature females generally exhibit a rounder belly, particularly when gravid. Males may be slightly slimmer and potentially show slightly more intense coloration under the right lighting. They should be kept in groups of at least 6-8 individuals, where the sex ratio naturally balances out.

Feeding frequency

Twice daily

Due to their small size and fast metabolism, they require frequent feedings of very small amounts of food. Feeding them two to three times a day ensures they receive adequate nutrition without fouling the water. Care must be taken to ensure the food particles are small enough for them to swallow easily.

Bioload

The Blue-bellied Night Wanderer is an extremely small fish that produces a negligible bioload in the aquarium. They can be safely kept in nano tanks or large groups without overwhelming biological filtration. However, due to their delicate nature, pristine water conditions must still be maintained through regular small water changes.

Flow

Stagnant

They originate from slow-moving, dark water habitats and strongly prefer gentle water flow in the aquarium. Strong currents will exhaust these tiny fish and induce severe stress. Sponge filters or baffled HOB filters are ideal for providing necessary filtration without creating overwhelming water movement.

Reproduction

Oviparous

Details regarding their reproduction in captivity are incredibly sparse, as they are a relatively new and rare species in the hobby. They are likely egg scatterers that require very soft, acidic water and dim lighting to induce spawning. Rearing the minute fry would require microscopic foods like infusoria.

Compatibility & tankmates

This is a remarkably peaceful and highly timid micro-predator that should only be housed with similarly sized, docile nano fish. Aggressive, boisterous, or large tank mates will easily outcompete them for food or view them as a snack. Excellent companions include dwarf rasboras, small tetras, and peaceful freshwater shrimp.

Tank level

Middle

These fish tend to occupy the middle to lower levels of the aquarium, often hovering near the substrate or hiding among vegetation. They are somewhat reclusive and appreciate a densely planted tank with plenty of shaded areas. Floating plants can help dim the lighting and encourage them to venture out more often.