Goldie River Rainbowfish

Adults reach up to 10 cm in length. Males and females show no obvious visual differences, though females may be somewhat smaller. The colouration is rich and varied, but blue tones predominate. A black stripe runs along the body and may narrow or gradually fade toward the middle.

The goldie river rainbowfish is native to southern New Guinea, where it is widely distributed. Its natural range includes many types of water: swamps, quiet backwaters, small streams and large rivers. Its typical habitat is dimly lit, with weak flow; the bottom is covered in fallen leaves and fallen wood, and aquatic plants grow densely around it.

During spawning, males often chase females persistently. These courtships can be very intense, and if the female has nowhere to hide, the pursuit may result in injuries. Keep them in mixed groups with 2–3 females for every male to reduce aggression. Outside the breeding season, intraspecific conflicts are rare. They are peaceful and get along well with other peaceful species of similar size.

The goldie river rainbowfish needs a spacious tank that resembles its natural habitat. The decor should include both open swimming areas and places to hide. Floating plants, branching wood or other natural and artificial ornaments help create these refuges. Use dark elements in the décor, including dark substrate, and keep the lighting dimmed. These fish tend to jump, so a tight-fitting lid is essential. They prefer soft, slightly alkaline water. Regular cleaning to remove organic waste, weekly water changes of 20–30%, and routine checks of the equipment help maintain stable conditions.

In nature, these fish feed mainly on small insects and their larvae, crustaceans and other zooplankton. In the aquarium, offer live or frozen equivalents and high-protein dry food. They feed in the upper and middle levels of the water, so uneaten food that settles on the bottom usually remains.

In aquarium conditions there is no clear breeding season. Females lay eggs among dense plant growth, attaching them firmly to the leaves. Fry usually appear within a week. The parents show no interest in their young, so move the fry to a separate tank to ensure their survival. Feed them with micro-foods such as brine shrimp nauplii, finely crushed dry flakes, or special fry foods.

Disease is rare when conditions are favourable. If you notice the first signs of illness, such as lethargy, body deformation or spots on the body, check the water quality first. Often, correcting all parameters allows the fish to recover on its own. If not, medication may be needed.

When selecting fish in the shop, choose active individuals with clean fins and no visible damage or coating on the scales. Healthy goldie river rainbowfish have bright colours appropriate to their age and show interest in food. Avoid buying fish that appear sluggish, stay at the water surface or have a sunken belly, as this may indicate hidden disease or stress from poor conditions. It is best to buy a group of 5–6 fish at once to reduce stress during their adaptation to the new tank.