Azurina

Azurina

The genus Azurina includes a number of beautiful, often bright blue or blue-gray reef fish that are part of the larger family Pomacentridae. These small, active fish are native to the tropical waters of the Indian and Pacific Oceans. They are known for their relatively peaceful nature compared to many other reef fish, making them a popular choice for saltwater aquariums. They often live in groups and feed mainly on plankton.

Name and meaning

The genus Azurina was first scientifically described in 1991 by American ichthyologist John E. Randall and Australian ichthyologist Gerald R. Allen.

The name “Azurina” is derived from the Latin word “azurinus,” which means “azure blue” or “sky blue.” This name is very appropriate, as many species within this genus have striking blue or blue-gray colors, reminiscent of the clear azure waters of their natural habitat.

As mentioned earlier, the genus Azurina belongs to the family Pomacentridae, the reef perch and anemonefish.

Characteristics

Fish from the genus Azurina are typical representatives of the reef perch, but with some specific characteristics that distinguish them. They are generally small in size and have a graceful appearance.

Here are the most important characteristics:

• Size: Most species of Azurina remain relatively small, often between 5 and 8 centimeters long. This makes them suitable for medium-sized aquariums.
• Body shape: They have a slender, elongated, and laterally flattened body. This streamlined shape is ideal for their life in the water column, where they often swim in the current.
• Color: As the name suggests, color is often a striking feature. Many species are a beautiful azure blue, bright blue, or blue-gray. Sometimes they have subtle yellow accents on the fins or around the eyes, or a lighter belly. The intensity of the color can vary depending on the mood of the fish and the lighting conditions.
• Fins: They have well-developed fins. The dorsal fin is long and continuous, with both spiny and soft rays. The caudal fin is usually forked, which aids in rapid movement and maneuverability. The pectoral fins are transparent and are used extensively for maneuvering.
• Mouth: The mouth is small and upturned, which suits their diet of plankton that they filter from the water.
• Scales: Their body is covered with relatively large scales.

These characteristics make Azurina species elegant and attractive fish that can be a beautiful addition to a saltwater aquarium.

Origin

Fish of the genus Azurina are true inhabitants of tropical coral reefs and are mainly found in the vast waters of the Indian and Pacific Oceans.

Their distribution range extends across a wide range of locations:

• In the Indian Ocean, they can be found around the coasts of East Africa, the Red Sea, the Maldives, and Indonesia, among other places.
• In the Pacific Ocean, they occur from the Philippines and Australia to the islands of Micronesia and Polynesia.

They usually live in the shallower parts of the reefs, often near steep walls, coral formations, or rocky slopes. They prefer areas with moderate to strong water currents, because there they can filter their food (plankton) from the water. You often see them in the open water column, just above the reef, where they swim in groups. The presence of many hiding places in the reef is essential for their safety.

The specific depth at which they live can vary depending on the species, but in general they are shallow water dwellers that you often encounter while snorkeling or diving.

Behavior

The behavior of Azurina species is one of the reasons why they are so popular with aquarium enthusiasts. They are generally active and lively fish, but differ from many other reef fish in their relatively peaceful nature.

Here are the main behavioral characteristics:

• Social structure: Unlike many solitary or highly territorial reef fish, Azurina species often live in groups or schools. You will often see them swimming together in the open water column, just above the reef. This schooling behavior provides protection from predators and is a beautiful sight in an aquarium. Although they live in groups, small hierarchies can develop within the group.
• Territoriality: Compared to their cousins in the Pomacentridae family (such as the more aggressive Dascyllus species), Azurina are much less territorial. They will rarely harass other fish, unless the aquarium is too small or there are insufficient hiding places. They may defend their own small spot on the reef, but this is usually not aggressive.
• Feeding behavior: They are mainly plankton eaters (planktivores). This means that they filter small organisms out of the water throughout the day.
  In the aquarium, you will often see them swimming in the current, where they pick small food particles out of the water.

• Activity: They are diurnal fish that are constantly on the move. They swim gracefully and quickly, always looking for food or exploring their surroundings.
• Hiding places: Although they like to swim in the open water column, they quickly retreat into the crevices and cavities of the live rock when danger threatens. Sufficient hiding places are therefore essential for their well-being.

Due to their peaceful schooling behavior and active lifestyle, Azurina species are a dynamic and relatively harmonious addition to a saltwater aquarium.

Care requirements

Keeping Azurina species in a saltwater aquarium is generally straightforward, especially since they are less aggressive than many other reef fish. However, there are specific requirements that must be met to keep them healthy and happy.

• Aquarium size: Although they are small, they are active swimmers and like to live in groups. For a group of 3-5 Azurina, an aquarium of at least 150-200 liters is recommended. A larger aquarium is always better, especially if you want to combine them with other fish. This gives them enough swimming space and helps prevent territorial conflicts.
• Water values: Like all saltwater fish, Azurina need stable and good water values.
  • Temperature: Between 24°C and 28°C.
  • Salinity: 1.023 – 1.025 SG (specific gravity).
  • pH value: 8.1 – 8.4.
  • Ammonia, Nitrite, Nitrate: Ammonia and nitrite should be 0. Nitrate should be as low as possible, preferably below 20 ppm.
  • Regular water changes (10-20% per week or two weeks) are essential to maintain high water quality and replenish trace elements.
• Decoration: Decoration that mimics their natural reef environment is crucial.
  • Live rock: Provide plenty of live rock with crevices, caves, and overhangs. This provides essential hiding places where they can retreat in case of danger or to sleep.
  • Open swimming space: Because they like to swim in the water column, it is important to also create sufficient open swimming space.
  • Sandy substrate: A fine sandy substrate is often desirable, although they are not directly dependent on it.
• Feeding: Azurina are plankton feeders, which means they filter small organisms from the water.
  • Provide a varied diet of high-quality frozen food such as mysis, artemia, cyclops, and finely chopped krill.
  • Dry food such as small flakes or pellets of good quality are often accepted.
  • Feed small amounts two to three times a day so that they can constantly “graze” as they would in nature.
• Current: A moderate to strong water current is desirable. This mimics their natural environment and helps distribute food throughout the aquarium, which stimulates their natural feeding behavior.

With proper care and attention, Azurina fish will thrive in your saltwater aquarium.

Reproduction

Reproduction of Azurina species in an aquarium, as with many other saltwater fish, is challenging but not impossible for the dedicated hobbyist. In general, they follow the pattern of substrate breeders, similar to other Pomacentridae.

Here are the general characteristics of their reproductive behavior:

• Mating behavior: Azurina species are likely to form pairs or live in small groups with a dominant male and female taking care of reproduction. In nature, they live in schools, and within such a school, pairs may separate to breed.
• Deposition site: They are substrate breeders. This means that the eggs are deposited on a hard surface, such as a flat rock, a piece of coral, or the inside of a cavity in the live rock. The male often prepares the breeding site by carefully cleaning it.
• Eggs: The eggs are small, oval-shaped, and laid in clusters. They are often transparent or light-colored and attach themselves to the substrate. The number of eggs can vary, but is often considerable.
• Brood care: The male plays an active role in brood care. After laying the eggs, he fiercely guards the clutch against intruders. He fans the eggs with his fins to provide them with fresh, oxygen-rich water and removes any unfertilized or moldy eggs. This behavior lasts for several days, depending on the water temperature.
• Larvae: After hatching, the larvae (young fish) are very small and planktonic. They drift with the current and feed on microscopic food, such as rotifers and later artemia nauplii. This is the most critical and challenging phase of breeding, as the larvae require very specific and small food particles.
• Breeding in the aquarium: Successful breeding in the aquarium often requires a special breeding aquarium, very stable water values, a varied and nutritious diet for the parent fish, and the ability to breed live food for the larvae. It is a project for the more experienced saltwater aquarist.

Observing this natural behavior, even if it does not lead to successful breeding, is an enrichment for any aquarium enthusiast.

Compatibility

The compatibility of fish from the Azurina genus in a community aquarium is generally good, which is a major advantage over many other reef fish. Their relatively peaceful nature makes them a suitable choice for many saltwater aquariums.

Here are the main considerations:

• Territoriality: Azurina species are, as mentioned earlier, much less territorial than many of their cousins in the Pomacentridae family. They will rarely be aggressive towards other fish unless the aquarium is too small or there is a shortage of hiding places. Even then, their aggression is usually limited to chasing.
• Conspecifics: They thrive best in a group of 3 to 7 individuals. Keeping only one individual can lead to shyness or stress. Ensure that the group is introduced at the same time, or add new fish to an existing group in a sufficiently large aquarium to minimize the chance of conflict.
• Other fish:
  • Suitable: They can be kept with most other peaceful to semi-aggressive saltwater fish of similar size. Think of other peaceful reef fish (provided there is sufficient space), surgeonfish (provided they are large enough), wrasse, gobies, blennies, and cardinalfish.
  • Points to consider: Avoid combining them with very large, aggressive predatory fish that could see Azurina as prey. Extremely shy or slow-eating fish may also be bullied, although this is less likely than with more aggressive reef fish.
  • Order of introduction: It is often a good idea not to introduce Azurina as the very first fish, but also not as the very last. They can be added after the most peaceful inhabitants are already established.
• Invertebrates:
  • Corals: Azurina species are generally “reef-safe.” They will leave corals alone and are not a threat to most soft and hard corals. This makes them an excellent choice for a reef aquarium.
  • Shrimp and crabs: They will leave shrimp, crabs, and other invertebrates alone. They are not a threat to cleaner shrimp, hermit crabs, or snails.
  • Anemones: Although they belong to the same family as anemonefish, Azurina species do not form a symbiotic relationship with anemones. They will ignore anemones.

Due to their peaceful nature and reef-safe status, Azurina species are a valuable and relatively trouble-free addition to most saltwater community aquariums.

Suitable aquariums

Due to their peaceful nature, active swimming behavior, and reef-safe status, fish of the Azurina genus are suitable for various types of saltwater aquariums.

Here are the most suitable aquariums:

• Reef Tank: This is the most ideal environment for Azurina species. A reef tank mimics their natural habitat with live rock and corals.
  • Advantages: Provides plenty of hiding places, a natural environment, and stable water values that are perfect for these fish. They will stand out beautifully among the corals and other reef inhabitants.
  • Points to consider: Make sure there is enough open swimming space, as they like to swim in the water column.
• FOWLR aquarium (Fish Only With Live Rock): This type of aquarium focuses on keeping fish with live rock, but without corals.
  • Advantages: Still provides plenty of hiding places and good biological filtration through the live rock. It is often slightly easier to maintain than a full-fledged reef aquarium, while the Azurina will still feel at home.
  • Points to consider: Water quality must still be high.
• Community aquarium: Azurina are excellent candidates for a general saltwater community aquarium, provided the other inhabitants are also peaceful to semi-aggressive and of similar size.
  • Pros: They add liveliness and color to the aquarium, and their schooling behavior is a delight to watch.
  • Considerations: Provide sufficient space and hiding places to prevent stress, especially if other territorial fish are present.

Regardless of the type of aquarium, it is always important to ensure:

• Sufficient space: As mentioned earlier, at least 150-200 liters for a group.
• Plenty of hiding places: Essential for their safety and well-being.
• Stable water values: The basis for a healthy saltwater aquarium.
• Good filtration and flow: Necessary for a clean and oxygen-rich environment, and to stimulate their plankton-eating behavior.

By choosing the right aquarium and setup, you can create a beautiful and healthy environment for your Azurina fish.

Species in the database

Below you will find the species within this genus that we have included in our database: