Gold Ring Danio (Danio tinwini)

The Gold Ring Danio (Danio tinwini) is a diminutive cyprinid native to the upper Irrawaddy River system in northern Myanmar, described formally by Roberts and Conway in 2009. It inhabits clear, shallow hill streams with gentle current, rocky and sandy substrates, and marginal aquatic vegetation.

Despite its small size (maximum 2.5–3 cm), D. tinwini is richly ornamented: the body is dark olive-brown to nearly black with rows of vivid golden-yellow spots arranged in irregular horizontal lines running from behind the gill plate to the caudal fin base. Under light, these spots shimmer with warm golden iridescence. The fins are mostly transparent with yellow-gold bases. Males tend to be slimmer and slightly more intensely spotted; females are plumper.

The Gold Ring Danio is part of a growing group of micro-sized danio species that have become increasingly available to aquarists in recent years, alongside species like Danio choprae (Fire Ring Danio) and Microdevario species. Like its relatives, it is an active schooling fish that thrives in well-oxygenated aquariums with gentle current.

In the aquarium, Gold Ring Danios are best displayed in groups of 10 or more against a dark substrate and background, where their golden spotting contrasts dramatically and the constantly moving school creates mesmerizing patterns of light.

Gold Ring Danios prefer clean, well-oxygenated water with gentle current: pH 6.5–7.5, hardness 5–12 dGH, and temperatures 18–25°C. They are a cool-water species that tolerates lower temperatures unusually well and may be stressed by sustained warm temperatures above 25°C.

A nano aquarium of 30–60 liters is suitable for a group of 10–15. Provide moderate current via gentle filtration or spray bar, dark substrate (black sand enhances their golden spots dramatically), and planting around the tank perimeter with open central swimming space. Fine-leaved plants provide spawning sites.

Feed small, varied foods: nano pellets, micro worms, baby brine shrimp nauplii, daphnia, and finely crushed flake. Their small mouths require appropriately sized food particles. Feed 2–3 times daily in small amounts.

Gold Ring Danios are entirely peaceful and suitable with other small, gentle species: other nano danios, small rasboras, small Corydoras pygmaeus or hastatus, small shrimp, and other nano fish. Avoid larger fish that may bully or consume them, or boisterous species that stress them.

Keep in groups of at least 10 for natural schooling behavior. Water changes of 20–25% twice weekly maintain the pristine conditions this clean-water hill stream species requires.