Domino Damselfish - Medium

Domino Damselfish

The Domino Damselfish gets its name from when they are juveniles they have a black body with 3 white spots, one on their forehead and one on each side of their upper back just below the middle of their dorsal fin. It matures into an aggressive adult whose bright spots fade with age often the spot on the forehead fades completely.

Juveniles have black scales with the centres being blue. Their fins are all black, though the spaces between the rays on their dorsal fin have a bluish colour.

These fish aren’t as speedy as other damselfish and so they will tend to stay closer to corals or caves where they feel safe.

The Domino Damsel is also known to change colour and make pulsing sounds when fighting, courting or caring for their nests.

The Domino Damselfish is among the easiest of all marine fish to care for. Being very hardy it is suitable for the beginner.

They can reach up to 5 1/2 inches (14 cm) in length, though 5 inches is more likely in the aquarium.

These damsels have the rare ability to tell the difference between predatory and non-predatory fish by the placement of their eyes and the shape of their mouths.

Domino Damselfish are hermaphrodites and all of them start life as females. The males are the largest dominant fish in groups. If the male dies then the largest female will transform into a male.

The Domino Damselfish have been bred in captivity but the young are difficult to rear.

Due to the aggressive nature of this fish, we recommend that you keep just one per tank or a male/female pair. They will work great in a reef tank, and really pose no threat to corals.

In the wild, these fish are found in various reef settings often in small to large groups of 3 to 25. Juveniles are found in very large groups with large sea anemones, sea urchins, or over small corals and live throughout the Indo-Pacific region.

Tank Recommendations for Domino Damselfish

The Domino Damsel needs a tank that is at least 208 litres (55 gallons) for one Domino. If keeping a male and female pair, we recommend providing a tank of at least 284 litres (75 gallons).

If you are planning to keep less aggressive or smaller fish than the Domino then a tank of at least 379 litres (100 gallons) or more with plenty of hiding places is what we recommend.

They aren’t fussy when it comes to the type of substrate, but rocks or coral that offer plenty of hiding places for shelter and retreat are recommended. Live rock with lots of hiding places, or even branching small polyp stony (SPS) corals are ideal. Having many places to hide will benefit both them and the other fish in the tank.

Even though these fish are durable, they can still become ill if exposed to poor water conditions for too long.

Suitable Tank Buddies

Choose tank mates carefully as these Damselfish get older they will be aggressive towards other Domino Damsels as well as other damsels and other fish that are not equally aggressive.

Male and female pairs need a large tank or may have serious domestic disputes resulting in injury.

Usually Compatible

Aggressive or large semi-aggressive fish make the best tankmates for these Damsels. In tanks under 379 litres (100 gallons), it's best to house them with large Angelfish, Butterflyfish, larger Dottybacks or other species that can hold their own with aggressive fish.

Sometime Compatible

Tankmates need to be as aggressive as the Domino's are, or much larger. So fish like Triggerfish, Batfish and Squirrelfish are usually okay with these Damsels. If you want to keep them with smaller semi-aggressive fish, like dwarf angelfish then the tank needs to be at least 379 litres (100 gallons) with plenty of hiding places for the other fish.

Rarely Compatible

Do not house them with fish who can swallow them whole such as Sharks, Rays, Lionfish or Eels. We recommend avoiding housing them with any predatory fish, even if they are not big enough to eat the Domino Damsel. This is because Domino's ability to recognize a predatory fish can stop them from coming out of hiding and eating.

Peaceful and smaller semi-aggressive fish will be attacked, especially in smaller tanks which rules out many Gobies, Mandarins as well as Pipefish and Seahorses.

Feeding Your Domino Damselfish

In the wild, these fish are planktivores that eat continuously. In the aquarium, they will adopt an omnivore diet. Accepting a wide variety of foods including pellet and flake foods as well as live foods like brine shrimp, Mysis shrimp and copepods.

If you are feeding them pellet foods then ensure to remember to soak them before you feed them to ensure that there isn’t trapped air inside them. They will also eat algae growing in the tank on the live rock for example.

We recommend feeding them at least 3 times a day.