Azure Demoiselle (Chrysiptera hemicyanea) M

Overview

The Azure demoiselle (Chrysiptera hemicyanea) is one of the most eye-catching marine damselfish available, prized for its brilliant electric-blue body and sunny yellow lower half. Small in size but big in character, this species is a popular choice for reef and fish-only marine aquariums where a splash of colour and constant movement are welcome. The medium size offered here is well suited to aquarists looking for a robust, active fish with a strong presence in the tank.

Azure demoiselles are hardy and adaptable, making them a great option for marine keepers with some experience of saltwater husbandry. They are generally straightforward to feed, tolerant of a range of conditions, and can settle well into a suitably sized aquarium with the right tank mates. Like many damselfish, they can become territorial as they mature, so careful planning is important. With the right setup, they can thrive for many years and become a real focal point in your marine display.

At Tropical Fish Co, we select healthy marine livestock and pack with care for fast UK delivery. Every order is supported by our live arrival guarantee, giving you added confidence when buying online.

Care at a Glance

Origin & Natural Habitat

Chrysiptera hemicyanea is native to the tropical western Pacific, particularly around Indonesia and nearby reef systems. In the wild, Azure demoiselles inhabit shallow coral reefs, lagoons, and sheltered coastal areas where there is plenty of rockwork, coral cover, and crevices to dart in and out of. These environments provide both food and protection, and the species is well adapted to life among complex reef structures.

Understanding its natural habitat helps when planning an aquarium. This fish is accustomed to bright, warm, well-oxygenated saltwater with lots of visual barriers and hiding places. In nature, damselfish often establish territories around coral heads or rocky outcrops, which is why aquarium aquascaping plays such an important role in reducing stress and aggression.

Tank Setup & Water Parameters

A well-established marine aquarium is the best home for an Azure demoiselle. A minimum of 120 litres is recommended for a single specimen, though larger tanks are strongly preferred if you plan to keep other semi-territorial fish. Plenty of live rock or reef-safe artificial rockwork will help create caves, swim-throughs and broken lines of sight, all of which reduce territorial behaviour.

Stable water quality is essential. Keep salinity consistent, maintain strong filtration, and ensure good water movement with areas of moderate flow. Regular water changes and careful monitoring of ammonia, nitrite, nitrate and salinity will help keep this fish in top condition. As with all marine fish, sudden swings in temperature or salinity should be avoided.

Recommended parameters:

• Temperature: 24–28°C
• pH: 8.1–8.4
• Specific gravity: 1.020–1.025
• Ammonia and nitrite: 0
• Nitrate: kept as low as practical

Because Azure demoiselles can become assertive, especially in smaller aquariums, it is wise to add them after more peaceful species or introduce multiple fish carefully in a larger system. In reef aquariums, they are generally considered reef-safe with corals and invertebrates, but their temperament towards other fish can vary with individual personality and tank size.

Feeding Guide

Azure demoiselles are omnivorous and usually easy to feed. In the aquarium they will accept a wide range of marine foods, including quality pellets, flakes, frozen mysis, enriched brine shrimp, chopped seafood, and algae-based preparations. Offering a varied diet helps support colour, immune function and long-term health.

Feed small portions once or twice daily, only as much as the fish will consume quickly. Like many active reef fish, they appreciate regular feeding and may become bolder and more confident when well fed. Including some vegetable matter or spirulina-based foods in the diet can be beneficial, especially for maintaining good condition and colour.

As with all marine livestock, avoid overfeeding, as excess food can quickly affect water quality. Remove uneaten food promptly and keep up with routine maintenance.

Tank Mates / Compatibility

Azure demoiselles can be excellent additions to the right marine community, but compatibility should be planned carefully. They are best kept with robust, similarly sized fish that are not easily intimidated. In larger aquariums, they can coexist with many reef-safe species, provided there is enough space and structure to break up territories.

Good companions may include clownfish, gobies, blennies, wrasses of suitable size, cardinals, chromis, and other moderately hardy marine fish. In reef systems, they are usually compatible with corals and many ornamental invertebrates.

However, avoid housing them with very timid fish, tiny species that may be bullied, or other damselfish in cramped quarters unless the aquarium is large and carefully arranged. More aggressive tank mates can also provoke stress and fighting. As a rule, the more space and rockwork you can provide, the better the chances of long-term harmony.

For best results, keep only one Azure demoiselle in smaller systems, or introduce a group only in a much larger aquarium with ample hiding places and a clear plan for managing territorial behaviour.

Why Buy from Tropical Fish Co

When you order from Tropical Fish Co, you can shop with confidence knowing your marine fish are handled by a team that understands the needs of saltwater livestock. We focus on healthy stock, careful packing and reliable service, with fast UK delivery to get your fish to you as quickly and safely as possible.

We also offer a live arrival guarantee, because we know how important peace of mind is when purchasing live fish online. Whether you are building a new marine setup or adding a splash of colour to an established reef, we aim to make the process straightforward, dependable and enjoyable.

Choose Tropical Fish Co for quality marine livestock, expert care and a smooth online buying experience.