Celestial Pearl Danio (Celestichthys margaritatus)

Common Name

Celestial Pearl Danio. Widely known by the acronym CPD and sometimes sold as Galaxy Rasbora. It is a true danio.

Origin and Habitat

Native to the Shan Plateau of Myanmar, with historic collections around Hopong near Inle Lake. The fish lives in shallow, very calm ponds and seepage wetlands that are thick with grasses and fine plants. Water is clear to tea stained, flow is minimal, and the bottom is soft mud and fine silt with leaf litter and tangled roots. Dense stands of fine stem plants and mosses make a living thicket where tiny plankton bloom after rains.

Temperature and Water Conditions

A practical aquarium range is 20 to 26°C (68 to 79°F). pH is commonly 6.5–7.5 with soft to moderate hardness. Stable conditions, very low nitrogen waste, and steady oxygenation are far more important than exact values.

Appearance and Size

A tiny danio with pearl-like spots scattered across a deep blue body. Males show brighter body color with red to orange in the fins. Females are fuller bodied. Adults reach about 2.0–2.5 cm (0.8–1.0 inches).

Diet in the Wild

A micro predator that feeds on zooplankton, tiny insect larvae, microcrustaceans, and fine biofilm.

Feeding in Captivity

Use high quality micro pellets and finely crushed flake as staple. Supplement with live or frozen baby brine shrimp, daphnia, cyclops, and microworms. Feed several tiny meals per day.

Behavior and Tank Setup

Peaceful and slightly shy. Keep in groups of 10 or more. Best in a planted tank with moss, fine-leaved plants, floating cover, and gentle flow.

Breeding

CPDs are prolific egg scatterers. Two reliable methods work well:

Colony Breeding

Maintain a large group in a heavily planted tank with moss, leaf litter, and gravel pockets. Fry will appear naturally among the plants.

Controlled Breeding

Use a small tank with spawning mops, marbles, or a grate. Condition with live foods, then remove adults after spawning.

Egg & Fry Care

Eggs hatch in 3–4 days at 24–25°C. Start fry on infusoria, rotifers, or powdered fry food, then move to baby brine shrimp.

Quick Facts

• Scientific name: Celestichthys margaritatus
• Origin: Shan Plateau, Myanmar
• Size: 2.0–2.5 cm (0.8–1.0 inches)
• Temperature: 20–26°C (68–79°F)
• pH: 6.5–7.5 (stability matters most)
• Temperament: Peaceful micro shoaler
• Diet: Tiny live and prepared foods

Tropical Fish Co. Notes

Think of CPDs as tiny forest birds that learned to swim. Give them a thicket of plants, soft light, and frequent small feedings and they will sparkle like a handful of stars.